To benefit from AA's leader ability, the only rebels you add, should have strong basic attacks. Otherwise, you will not benefit much, if an attacker with a weak basic is called by the leader ability. Leia's basic is outstanding, which means that she should be the only other rebel. To trigger the leader ability and possibly activate you want to add charachters with good non—attacking abilities, f.ex. Phasma or RG. I believe on defense, AI uses Phasma's aoe/slow ability before her VM, however. AI always uses RG's buff when possible.
....Unless, of course, you want to make a full rebel squad, just for fun.
