I agree in liking battle for the way it is, and that's why (I think it's like post 6 or so) I say that this addition isn't Detracting from Battle mode (at least for the first 2 or 3 minutes).
The goal, technically, first and foremost, is to kill the other guys (as with every mode in this game). However, the addition to having a place that a team NEEDS to be, otherwise a loss is ensured, will make less draws, and put a little more purpose to killing the other guys. That's why a static time is suggested (albeit the possibility of having it slightly random, say the 2 minute mark one round, and the 2:30 minute mark another round, etc...) to make it so that Wiping the other team is still a very viable, and easily achievable option. I've seen servers with 30 people per team, where within a minute and a half, it's become just hunting for the one or two stragglers that decided to Not go with their team.