COO already stands by your boss side.

COO is the one to keep you busy so that you won't be able to manager your team. You should either leave or just work with your boss. Your boss may have a different view from you. COO hired your boss, to him, your boss is more valuable than him. If you want to stay, then you need figure out a way to work with your boss. Change doesn't mean bad. Don't think you are the only smart one.