I run droids and with HK lead, I rely on AoE not just to grind the enemy down but to increase my speed. @awbattles has the right idea. With HK lead whenever I land an AoE (which GG, 88, HK, 100 and B2 all have) I'm pretty much guaranteed a second shot. I've listed the sequence I get when I swap out B2 for JE on another droid thread, but it basically means I can get up to 9 attacks before the other team gets their first.
I'd argue there is no better AoE synergy in any other combination.