I feel like all maps should be the exact same size
A big part of talk about balance I feel is generally that on some maps a killer/system might not work as well as on others, due to the size of the map, distance apart on doors, etc. So why don't you just make every map the same size? It feels like this would make balance a LOT easier overall. Sure, it might take a lot of extra work on the smaller maps, but in the end, it feels like this would make things easier to balance in the long run.