You don't really NEED any accuracy, since almost all of the damage will be tech attacks (which players have no innate resistance to, unlike raid bosses)
I'd say around 25% crit should be pretty good, and on Tuesday they're giving us a +6% crit buff
I use 2 field medic (+10% shield probe) and 2 old PvE pieces (+15% Back Blast crit) for set bonuses