I have to admit the trees look rather simple, but that's more of a texture problem. It's very hard to find good tree textures with transparency, not to mention making your own.

About the mesh terrain: I'd rather make everything in a 3DCad and export to unity than to depend completely on unity based assets. It helps me to keep the polycount under control and optimize it. I think you mean that the terrain is made up of only one texture. Don't worry about that, it will be improved once I know how to do that perfectly. Same thing with the track textures. I usually leave those details to last...

But I seem to be under the impression that you expect something like Wipeout HD from us. You have to keep in mind that we are a bunch of amateurs with almost no resources and time, unlike SL, for example... You gotta think to yourself what you would expect from a hobby based free indie game... I would aim around an enhanced Wipeout Pure...