Some ideas.

[Mishqutin]

Hello.
Sometime ago I was tuning my car. I wanted to see how it will behave with stock wheels. I disliked that tune so I put it back to race setting and I needed to buy it again.
And my idea is: Store purchased parts in garage and ability to change them in safehouse, sell them.

My second idea is to improve police pursuits. The evade/busted bar should go to the left only when driving below e.g. 30km/h. After Shift+x it should start from half to the busted to prevent cheating or something. Also the police cars' behaviour should be changed. When it is chasing me and hitting my back it only touches me making a small effect. It could hit me that hard that I will turn at least 90 degrees.

Third idea is about car damage: Car recovery should regen car's health or spawn a new vehicle due to that I can crash onto gas station and blow my car up. Then anything I can do is go back to safehouse by F6. There could be a "Car damage" checkbox in settings. It would make visual damage but not to vehicles health. And I've seen a little bug: Sometimes I hit something with car's lights it does not repair. I think there could be a script: if body damaged then repair all the body. Maybe it works like I said but the game just doesn't count broken lights as damage.

And the fourth idea is to make vehicle control panel. Only on freerun. E.g. hold shift or other key and press numeric keys to toggle lights, engine, open doors/hood/bootlid.

Fifth: Colored burn slicks. Burns your tires on green, pink etc.

[YoWorstNightmare]

Well, when the police hits me i feel like i've been hit by a bus or something.

All other suggestions are pretty nice, i'd love to have them ingame.

[Quindo]

Car damage: the fix for nor repairing headlights is ready, will be added in update. There will be no visual damage, because models on server don't even have damage model.
Vehicle control panel: it's a good idea, it was already discussed between team, and may be added if someone finds time to script it.