This game can be so much more, and i think these stuff can help it:
Having complete tire choice
Basically, Forza has the rights to put Goodyear, Michelin, Pirelli and other brands tires in the game, but this can be done only in certain cars. All these tires should be available for purchase in every car (i personally wish for NASCAR vintage Goodyear tires)
Having an actual Pit Crew
I know it would take a ton of work but a smart way to do it, it’s by only allowing some cars to have crews, like LeMans, F1, NASCAR etc.
This is probably very obvious, but one thing that i would pay for, is to have old school racing, especially NASCAR. The old muscle cars in the game are all street version, an amazing thing could be having a certain upgrade where the body becomes really stock (no doors, no lights etc.). Or another way to do it is to have a completely different car (example: Dodge Charger Daytona and #71 Dodge Charger Daytona NASCAR, like in this photoshopped picture) that is an iconic car for NASCAR and has an insane top speed (about 217mph). I think old school NASCAR enthusiast would love to race these cars in modern racing (another example is the Chevrolet Montecarlo NASCAR)
This is already something in the game, like with the Chevrolet SS (street version) and the Chevrolet SS NASCAR, same for the Ford GT, and Ford GT LeMans
Having drivatars in multiplayer
I’m expecting to see this as Forza Horizon has it already, but it sure is a feature needed for small group of friends deciding to make a private lobby
Safety / Pace Car gameplay
If online, and with a Pace Car, i think we would all love to do some roleplaying with it, and putting this in the rules would make drivatars understand what’s going on
Being able to make other people / drivatars race a specific car
This could be a very nice thing to do, as drag races and races against drivatars and players would be completely customizable
Public lobbies and Multiplayer penalty system
We all want public lobbies, multiplayer in Forza 7 is not the best (love the airport freeroam tho)
We also all want a good penalty system, and a good way of doing it is maybe preparing some presets rules based on real motorsports. This can be related to the Safety Car gameplay, example:
You are about to start a Daytona race, and putting NASCAR rules means the first x laps are with the Pace Car in front, then green flag, cautions etc.
Sound in general in racing games it’s hard to do but i will keep hoping for insane V8 sound, loud flybys etc.