Between the newer Challenger and the older Charger, I would be profoundly surprised if we don't end up getting an Extra Menu featuring various Dodge models. That is, aside from the Viper, which we already had a menu on.
I could see there being one for classic Dodge muscle cars, featuring this upcoming classic Charger, as well as the Super Bee and the older Challenger.
Then, I could see there being a Lexus-themed Extra Menu, with the LFA, RC F, and LC500. Perhaps there also could be a Nismo-themed Extra Menu with the 400R, GT-R Nismo '17, and perhaps a race car like one of the two GT-R GT3 models, or maybe even the GT-R LM Nismo LMP1 racer.
EDIT: This is before we potentially guess new rounds for World Circuits events, too. The LFA will likely lead us into some new Hypercar Parade events, while the newer Challenger and older Charger could get us some new rounds for either the American Sunday Cup 600, American Clubman Cup 700, or both. For the new 911 GT3 RS, I would be quite surprised if it didn't result in a new round for the Porsche Cup. Can't say I know of if the Model III will lead into anything - perhaps a new event for EVs? Finally, I really don't know what could come of that Mercedes-Benz model. If, hypothetically, it's the DTM racer from the early 90s, then it'd likely go into Gr.4 like the Alfa Romeo 155, and thus could get us a new WTC 700 round. If it's the road car, then I suppose it could lead into new rounds for the European FR Challenge 550.
Of course, we could get a new Bonus Menu as well, featuring an all-new event. Maybe even a new championship - one that uses one of the more advanced licenses. This is before we get into the possibilities for new tracks and/or missions. (I'm also still a bit surprised we don't have a Super Formula round at Suzuka yet.)