The juggs will be your best bet for pvp.

If you want to do pve, then 3 juggs and a sorc will work great to keep your pvp and pve teams almost the same. Also, 1 Jugg and 3 sorcs will rock for pve as well. Sorcs in pvp will be extremely difficult and I wouldn't bother trying it.

4 juggs in a pvp warzone will be very challenging but doable. It gets tricky when one dies... you have to control him individually while the other three are in combat otherwise the afk timer will kick him out of the warzone.

The operatives are the weakest class for multiboxing. If you go sniper with two of your agents then you can substitute them into your pve team for awesome ranged DPS.