After some time to marinate in the teaser... I think I've finally settled on a formal prediction. I think it's gonna be that focus on marketing partner tuners I'd neglected to look into before; the more I think about it in combination with everything else I've seen and figured, the more sense it makes. I hate that I actually have to look into it now, but at least it'd be worthwhile, moreso than the modern off-road focus of Modern Horizons.
In short: I predict the theme of the car update will be "Icons of Car Culture." The entire update will be something of a celebration of modern 'dudebro' car culture in a way that just having another Donut Media update wouldn't fully permit. They won't have any one tuner as a focus, but instead they'll shine a spotlight on all of their major partners up to now--that would be Chris Forsberg, DeBerti, Hennessey, Saleen, and possibly Mercedes-AMG, should they also count, but I'm mostly leaning towards the first four. Donut Media will get the car pack, and I'll probably copy-paste that over to complete the prediction--in a way, this pretty much IS Donut Media Part 3, just not in the manner we expected.
Icons of Car Culture (or, A Meeting of the (Automotive) Mechanical Minds)
Series Reward: 2022 Hennessey Venom 1200 (80 points, New-to-Forza; unchanged from last prediction)
Summer: 1965 Deberti Design Chevrolet C10 Slayer (20 points, New-to-Forza; this is the last major DeBerti restomod not in Forza I think, so it makes sense for this to come in for this update)
Autumn: 2003 (?) Chris Forsberg Nissan 350Z Drift Car (20 points, New-to-Forza; Forsberg doesn't have that many cars it turns out, so this is a tossup between this and his 370Z with the SpeedHunters livery, but it's up there for me.)
Winter: 2024 Saleen GTX Tesla (20 points, New-to-Forza; Obligatory EV Pick, also a good way to get around Tesla), 2007 Saleen S5S (Returning, either 40 points or in an Exclusive Event)
Spring: Mercedes-AMG GT 4-door Coupe (20 points, New-to-Forza; side grade to existing car that PG frankly does love to do)
Last, but absolutely not least, the car pack; Donut Media's got this, I can't imagine anything else right now.
Donut Media Car Pack ($9.99)
1998 BMW 328i "Money Pit"
1994 Mazda Miata "Money Pit"
2002 Toyota Tacoma Pre-Runner "HiTruck"
2002 Toyota Tacoma Pre-Runner "LoTruck"
2005 Subaru Impreza WRX "HiCar"
2005 Subaru Impreza WRX "LoCar"