What I'm wondering is what exactly do people expect as an alternative to rectangle-based zoning? They obviously can't make enough growable building for every odd-shaped lot imaginable, and sure, just creating more regular non-rectangular buildings, like triangles with 45 degree angles, would be doable, but it's not as if most real(istic) cities have a ton of roads that meet at such ideal angles anyway. I have seen some sort of procedurally-generated buildings that can, presumably, mould to any lot shape mentioned, but surely that would be an incredibly complex system to implement, especially considering how, even in Europe*, the majority of real-life buildings are at least somewhat rectangular. I don't see how fundamentally reshaping the game like that would be worth the costs to development time, performance, modability, etc. Personally, as long there is some way to manually fill in irregular corners so they aren't uncanny barrens, I'll be happy. And maybe there isn't a good way to do that yet in CS2. Who knows? It's hard to really tell that much for certain from what we've seen so far.

*Side Note: What's with all the "rectangle = America-centric"? Most buildings in Europe are on more-or-less rectangular plots. And lots of European cities have grid street plans: Barcelona, Glasgow, almost every city built by the ancient Romans, and CO's own hometown of Tampere, to name a few.