The crashing is already good enough, but I would like for there to be damage textures as well. It doesn't feel realistic when you don't see a single scratch on your car after a 60+ MPH crash. I would like for there to be burn textures too.
Theres a way to do it, but that would require more coding, If I had the time I would explore it more and try it out. I think this a feature that will be added but its on the non-essentials list for now.
If I were a bettin' man I'd say a lot more than just burn textures are being thought about. Getting them implemented correctly is the time consuming part.
Vertex blending of textures should really be a top priority, it would allow for damage textures, scratches, dirt, and burn marks, and maybe even ingame decals.