1. Car list: The entire Forza series has 1361 cars in total, including hidden pre-order cars, the Null Car and the Fallout Chryslus Rocket 69 2077 (as of now), might as well re-model the rest of the missing ones from previous games into Forza Motorsport 7 while adding the new ones coming from Forza Horizon 3. Apparently more diversity in terms of historic race cars, rally cars (WRC, Group B, Hillclimb and rallycross) as well as the Blancpain Endurance Series, touring car leagues such as the WTCC, BTCC, etc., the European Truck Racing Championship, other open wheel leagues such as US F1600, Indy Lights, IndyCar, classic, retro and modern Formula One, the Bondurant Formula Mazda series, NASCAR, drift (D1GP and Formula Drift), JGTC/Super GT, Group C prototypes, DTM and several concept cars should come. With plenty of rallycross, WRC and hillclimb cars, it would make sense for rally tracks as well. Obviously all cars must be available in the Dealerships and as rental cars in Arcade/Free Play. So far, count all the cars that made it to Xbox One and you'd be looking at around 580-600 cars. My copy of Forza 6 seems to have 606 cars already. Hopefully, if all the cars in the series are returning, people who desperately want the S14 can finally keep their mouths shut and just call it a day. Believing the fact that in every Forza game, as graphics get slightly better, tessellation should be part of the game on every car. Considering Forza's inspiration from Enthusia, car diversity is king.
2. Tracks: The entire Forza series so far also has 272 tracks within 50 environments (as of now). This could also increase with Forza 7's release. Forza 6 so far has 112 tracks within 28 environments. That is more than twice as much as GT6 in terms of tracks, and if all real-life tracks are laser scanned and every single track in the game receives dynamic weather and time settings, that would be really great. Tracks I would personally want to see are Autodromo Enzo e Dino Ferrari Imola, Circuit de Nevers Magny-Cours, Autopolis, Willow Springs, Circuit Paul Ricard and Fuji Speedway, as well as two well-known WTCC tracks such as Hungaroring and Slovakia Ring.
3. Arcade/Free Play mode: Forza 6's arcade/free play mode is no doubt the best in the series as you can recreate races from the career mode, but it has some flaws, hot lap mode isn't there and drag racing is no longer available. Would make sense for them to return, as well as warm-ups, practice and qualifying before a race, as well as a serious, separate drifting mode similar to GT6 as opposed to a simple, yet boring Drift HUD. Penalties should come in a similar vein to F1 2015 with an option to turn on penalties and the severity of them, which could teach these Drivatars a lesson never to mess with you, and to add elimination as an aspect of the racing in Forza. Car Soccer and Tag (Virus) must return in a similar manner to Forza 4, but also available as a single player mode a There should also be an ability to randomize every selection. 2-player split-screen should also be supported on PC, whether it's a desktop or a laptop, considering future Forza games starting from Forza 6: Apex would also be on PC through Windows 10. And with that, LAN multiplayer should also be on the PC version of Forza Motorsport 7. Just like in the previous games (2, 3 and 4), you should be able to create tuning set-ups for cars in Free Play mode and to choose the color in a similar manner to Forza 6 Apex, like you can select the manufacturer's factory colors on a car, choose any color from the game's entire color palette like in the livery editor or even use saved and downloaded liveries onto any car you've used them on.
4. Physics: The physics in Forza, to be honest is a little bit slippery and a little bit arcade-like despite being derived from simulators, thus resulting in a strange hybrid. It's time they changed and overhauled it, as there are three common ingredients for a racing game's physics: drivability, car specs and damage. Some car specs are a bit incorrect (but there are plenty to name). If they re-programmed the specs into realistic versions, added compatibility for KERS and DRS on most cars as well as beefed up the damage model a little bit (similar to Forza 2, but with the ability to totally destroy car systems and get eliminated, similar to Project CARS and the Grid series) and made the physics like Enthusia/Assetto Corsa, but also user-friendly, everyone's gonna love it, from the average gamer to the typical, seasoned pro, or "Forzisti". There should be an option to use the realistic driver aids on every car (for those who don't have them, then they won't be used) and with the simulation of realistic automatic transmissions as a separate option.
5. Forzavista: Forzavista must go back to its Forza 4 roots where it was so detailed and would actually give you a sense of how that car really works and interesting facts about it, and with Forza 5 and 6's new functionality. Yes, that would mean that the narrator would have to provide a speech for over 1400+ cars to keep us entertained. Or probably a text description instead as that would take a lot of development time. Forzavista should also have a museum mode with the history of every manufacturer in the game. I mean even Forza 4's Forzavista even shows some components of the car depending on which aspect you view Forzavista from. That's how detailed it was but only had around 20-30 cars available in Forza 4's Forzavista mode where it was still called "Autovista".
6. Online: There should be an Open Lobby mode which is exactly like Arcade/Free Play mode, where all the cars in the game can be used as well as garage cars, although online, and keep the rest of the online features from Forza 6 although with the return of the Storefront and Auction House from the previous games.
7. Customization: This would mean having to return all visual customization parts (everything from custom wheels, aero and appearance parts as well as all livery editor items) back to the game and bring in more advanced ones, as well as the fact that tuning the performance must be the same as in Forza 4/Horizon/Horizon 2 for most cars to get the most power, handling, weight reduction as possible from these cars. Air restrictor mods should just be part of tuning set-ups instead of a purchasable upgrade ( and the tuning set-up creator should just be like that of Project CARS. Nitrous must make it to the game, although portrayed realistically like in GT6 (Forza Horizon 2's Fast and Furious standalone game featured nitrous, but was unrealistic, considering nitrous in reality won't produce a sound and thruster flames from the exhaust).
8. In-game player character: Considering the fact that Forza 6 allows you to play as either a male or female character, you should at least be given the ability to customize your racing attire individually from the racing suit to gloves, shoes, and helmet (a la GT6), or play as your own Xbox Avatar (despite the fact that it will look weird, but fun.)
9. Levelling and rewards: I think returning to the Forza 4 in-game rewarding system (where you level up, you get Credits and one free car out of a selection of certain cars) as well as Affinity where not only where it will earn you money, but will also give you discounts on parts (down to the fact that almost all performance modification parts are free) and one new added bonus: you can get car discounts (down to the point where the price is 50% lowered), making it easier to build a collection especially if you're going to make a lot of custom builds, considering that Forza 6's in-game currency and economy is good enough.
10. Home spaces: The home space in Forza 5, which looks like the garage of a mansion, as well as the home spaces in Forza 6, the one in the penthouse in Rio and the race paddock, should return as home spaces along with new ones for enhanced photo mode. This is like Forza's version of GT's Photo Travel mode.
11. Menu music: Main menu soundtrack in Forza 3, 4 and 5 were composed by Lance Hayes (a.k.a. DJ Drunken Master), whose menu music in Forza 3 and 4 were really good, but then in Forza 5, the menu music he composed is weak techno/lounge with an orchestra singing something that goes like a lot of "AAAAAHHHH" and there's one with "KAMEHAMEHAMEHA". The menu music in Forza 6 is composed by someone else and is a little bit livelier, but still puts you to sleep. The main menu music should go back to its Forza 3/4 roots where it is both lively and would make you enthusiastic to play the game, or just used licensed music as menu music again like in Forza 2. Either way that is better than having menu music that would put you to sleep.
12. Pitting: Making pit-stops for both the player and the AI should also have pit crews and an interactive way of pitting in, like in GT6.
13. DLC Scheme: The DLC scheme must be similar to Driveclub where it lasted a long time and with a season pass that lasts for about a year that will be able to deliver the best of the goods, as well as abundant car and track expansions with varying amounts of content per pack (as opposed to only seven cars per monthly pack), probably a little bit more but it's always good to add in extra stuff. In some cases according to some people, the DLC scheme of Forza (especially with 5, Horizon 2, 6 and possibly, Horizon 3) may feel like a bit of a steal.
14. Some stuff in the Forza games that must die:
a. "Unicorns" (a.k.a. "community bounty cars"): Not a lot of people can use Xbox Live Gold or actually play online, or may have trouble reaching a certain limit to get them, so these must be ruled out and must be released as free cars as part of a game update. The worst may have to be buying Furious 7 on Xbox Video to get Dominic Toretto's Charger from Furious 7 or actually having a save of Fallout 4 to get the Fallout Chryslus Rocket 2077. And it's a shame that the Lamborghini #63 Squadra Corse Huracan LP 620-2 Super Trofeo '15 is one of them and yet it's a new car. And possibly even the Ford Escort Mk.1 RS1600 '72 as well. All the unicorn cars or "community bounty cars" from all the previous titles should return as regular cars and this system of bringing in certain cars every month should die.
b. Tokens: Microtransactions in Forza, especially in 4, Horizon, 5, Horizon 2 and 6 are a pain despite it being a full, premium game. The cars and items in the game are cheap enough already and the fact that it is easier to earn money, considering if you have the VIP DLC.
c. Removal of VIP: The VIP DLC stuff must end. In Forza 6 all it does is add double your cash and XP if I'm not mistaken, and also access to VIP-exclusive Rivals (Forza's version of seasonal events). Not a lot of people would be interested with this, and some think of this as an incentive to get the best benefits of the game for just a price. At least the Car Pass, free cars and the expansions can stay. With the VIP DLC removed from the Forza series for good, the economy of both credits and XP will have to be increased quite a lot to maintain the player's needs of levelling up for improved perks and buying cars and customizing them. However, this will result in equality for all players.
d. Horribly evil and idiotic Drivatars: This has been one of my complaints playing Forza 6. Even with the "Limit Aggression" setting, Drivatars are like wild zoo animals that are actually driving and are still as bankrupt in terms of aggression. Like I said, with the aggressive AI, wanting to smash your car off the road or blocking you like crazy, they will tend to piss you off. And in the earlier versions of Forza 6, the front of the pack are seen to be cheating and driving like in a capability that you cannot imitate or even perform better while in the car they're driving, which is unrealistic. They also tend to drive like idiots as well if you'd put a lot of pressure or if you rewind a lot. The Drivatar system needs to be completely overhauled, and with a setting to return the typical Forza AI with generic names of drivers like in the previous games. Drivatars should also be able to drive DLC cars as well, but then this will only let them drive the Null Car if not installed, and considering that in my opinion, that I want the Null Car to be part of the car list as a useable car like all the other cars in the series, maybe it should be an invisible generic car silhouette for AI cars driving uninstalled DLC cars.
Put all of this together and now what we need left is proper wheel support and probably a good career mode to go with that. Porsches since EA's license could be expiring this year would probably result in Forza 7 having Porsches at launch, I guess. This would ideally outclass GT6 and Project CARS in every way if this happened for Forza 7. I'd say the car sounds are good already, in fact. In my honest opinion, starting with Forza 5, the Forza series had really clear and almost realistic graphics out of any game I've played, so that should not be a problem.