Agreed on the asteroids, without much balancing work I think they mostly just serve the purpose of ensuring you don't build a mega-massive cluster all at once. Not sure if I would keep them long-term or try to find a more compelling 'antagonist'.
Yes! They're part of a cellular automaton updating 10x per second. Iteration order is randomized so that they're not always moving in a single block, and there's a 5% chance for any given bot to move in a random direction each update, regardless of input. Glad you liked it!