When the world is too overcrowded and where laywercats can't respawn, I would suggest to enlarge the world or another new world with differrent biomes like tundra,desert or just the old one.
The world is not crowded (yet), but there's still (very) much time to develop the game. So my idea is low priority.
Or just have a teleporter in town that sends you to a place that's impossible to build on, so that there'll always be a place for lawyer cats. It could be a place you can't get to by walking around - you'd have to teleport.
And/or there should be unbuildable areas in the regular part of the game.