Items 1-3 are inadvertently caused by how I made the targeting work. I have the protection turrets on a different team than the players and just make that team friendly with players. The turret changes the team of the targetted spawner to one that the player is not actively hostile with, and that's how I prevent the other turrets targeting the spawner. The spawner protection laser has to be on a separate team from the player that remains hostile with the lazed spawner with this method. Bots should be able to place the turret still, but I do think blueprints might misbehave. I didn't notice this and agree it's a problem. I'm not sure what I can do about it, but I'll explore.
Item 4 is mostly intentional. I wanted the turret to be at risk, and if the range is too long that gets too simple and you can run into it targeting the wrong spawner, maybe I need to add some alternative methods for the active capture part of the gameplay to make that more fun.
Item 5, the difficulty is 100% intentional here, I can recommend giving the turret its own micro-grid!