Add me to the list of people that love the concept. Did you ever play the multiplayer boardgame version?
I remember I was really excited as a kid when I first got it, but it was really hard to get an even match going... it becomes unbalanced very quickly as someone would always gang up on player 3 (typically my younger brother) while the 4th hangs back and then swoops in when everybody else is weakened. I guess it just goes to show waging war on multiple fronts is hard!
I think it'll work much better as an online video game with the anonymity of the internet, and if you're the first to get knocked out you don't have to wait around and can just go find a new game.
Still, I can see it being a big design challenge. Looking forward to seeing what you can come up with!!