Not seeing 2000 of the same skylines
More cars not cars centered around Japan, which at least 70-75% of them were
Realistic car engines sounds
Engine swaps
Better races, GT3 with more races
Better AI racing them is like a snooze fest ex: because they slow down as soon as you pass them even on a straight away.
Car customization

Motorcycles For sure! that would be awesome!

open roads like highways and stuff

Full on "Drag strip" more rims, decals and more ozzy carsD=

i would love to have cars from smaller sometimes unknown makes such as the ascari a10 and would love it if they could incorporate a few open world rally point events similar to cannonball run. i agree with previous comments about vehicle customization as it gets pretty boring seeing everyone in the same cars just different colours.

I agree mostly with what everyone else added. Though, I would like to see more tracks, more f1 cars, and if they could bring indy cars to the game I'd be a happy camper