I like the idea Bruv, but if I may...
I think it would be better if it was sort of like furball lake, in the sense that once you die you can immediately take back off again and join back in on the squad duel. And a round is basically 10 minutes non stop or something to that effect. With that, have there be an area in the middle that you must stay within if you aren't engaged and have "survived". The reason for that is so a couple guys left can't retreat and reform with their reinforcement squaddies past a certain point in the middle. After the 10 minutes most kills wins.