Things like Driver Rank / Safety Rank would make a huge difference. Other racing titles already prove that these systems create a much better online environment.
The license system currently in the game already does this. You start out at rank C and can rank up by driving clean and rank down by driving dirty. The system then attempts to match drivers of a similar rating together.
Also, we really need a Radar system like in other racing games.
It's an interesting idea, but I feel like adding a radar might be a bit divisive as some players will say that it's not very realistic.