The rain looks really good. And the lightning in the clouds is a great touch. My only complaints:
1. The clouds are too sparse for how heavily it's raining
2. The sounds of traffic and thunder seem to be coming from the UI rather than being spatialized. It would be nice for the thunder to sound as if it's coming from up above.
3. There's no way to return to the map if I parkour out of bounds.
The controls are a bit clunky and hard to wrap my head around. The systems being simulated are cool, and have great potential for goofing around. It's fun to explore the matrix of possible interactions.