As you have been building crannys to stay alive.there comes a time you need other buildings as well.
Frsit you have to build your main building up to level 10.
Then you can remove buildings ya don't need.You will louse the stuff in them buts it well be ok.
If a cranny is level 10 ya have to take it down one level at a time till its gone.then you will have a open space to rebuild.
And the same way for all your building.Sometimes its is needed when a heavey attack comes on you that you can take a low level building away to put a cranny in it space before the attack comes apond you.But only if its an attack from far away that will give you time to do that.Its a handy tool on the game.