Honestly with SK/Shm/Zerker, your best option is bard, their indv dps is low, but the ADPS it will do will be immensive for the other guys,
or if you honesntly dont want to farm anymore Hdex augs,
Mage atm is a solid choice also has a one of the class plugins,
SK/Shm/Mag/Ber would work, then...