Why would you disable other people's admin just because you came in? To make it clear that you wear the daddy pants around here? If you can trust them to not abuse when you're not there why would you take it away when you can actually watch them?
My suggestion to make this a very useful plugin is to design it to solve the pervasive problem of admins playing map tug-o-war. How it would work is you'd have a ranking system and only the highest ranking admin in the server can change the map. Also NO admin can come in the game (except #1 ranked admin) and change the map until they've been in the server for at least 2 minutes. That's just my 2 cents.