This is a small suggestion but one that might help avoid the base cubes with insane amounts of doors!
People have a habit of protection there base by making a labyrinth of doors or having to do this.
My suggestion is to make doors get bonus hp depending on how big the base is and then dividing the hp bonus with the amount of doors you have in the base.
The only thing that i have not yet figured out is how to prevent the hp bonus form redistributing when one door is destroyed
Maybe people have some good solutions for that problem?
What do you guys think about this idea or do you have a better alternative?