Development slowed down a bit - since July, I mostly worked on AI. It can now avoid obstacles and/or other cars. The biggest problem was avoiding head-on collisions.
Then I had almost two months of a break, until a brainwave hit and I worked a bit on the assets instead.
A bit of shader magic for the signs, some texture editing for the lanterns, more window color variants, and a bit of procedural modeling again to create storefronts on the ground floor (the textures are from a public domain set, and I applied some shaders to them, too)
Unfortunately there's not much winter this year where I live, but I implemented snowy ground material and snow particles, and snow/smoke/dust effect. I also added skid marks, which have long been on my wishlist.
The main game is mostly done now, the majority of the things left on my wishlist are pretty much optional (such as adding some clutter to the streets, or roundabouts and more race types and multiple AIs in a race...)