My suggestion would be to make burst shots ignore AC - you just can't dodge all bullets.
And add -AC to ammo like rockets and grenades.
There is already -AC for ammunition, it's called AC modifier, though it's zero for half of the ammunition out there or set quite low.
edit:
Hmm interesting, maybe armor class could be balanced out mostly by adjusting ammunition modifiers or at least partially.
First of all, at most, there was only 2 waves of enemies last session unless some crazy preparations.
Let me see, from the community thoughts i've been playing some time with the biggest cheaters, abusers, hackers and what not they have been called, cool people actually, i remember only 1 wave of alts, rarely second that consisted of only few people in the best case scenario who actually waited those 3 minutes to log into another character upon dying. That timer was effective to prevent PvP going complete marbles, no matter what players say, proxies are not suitable for waves because all free proxies lag like very much and tend to crash frequently, second of all things considered those players who did break rules and did second waves were some small irrelevant cells who just best to ignore because they didn't spoil the gameplay for others in the grand scheme of things, hardly at all.