Fuel + Health, in that situation it'll get rid of any possible real op'ness, because the only bonus it will give is to make your chance of living longer better; on top of that there will no longer be any differentiation between the bonuses for the bot types, so no one will be able to take advantage of anything that someone else can't. Finally when you add the fuel in to it you make it so every round you are risking an amount of your bs, so people would be more careful about using it, and there'd be less to go around.