Just have the whole guild put resistance on farm. 5 of you can take out p2, 10 of you can easily take out p3 (with r2), and another 5 can take out p4 (or solo if you have bb8). They aren't good at p1 but you can either throw the kitchen sink at it or work on zeta kylo.
You will also find that everyone can 6/6 a light side battle for every TB phase as an added bonus.
There are probably easier ways to get there, but if you want simplicity it is hard to find a team that is more useful than resistance across three phases of HAAT, and that will also change everyone's life in TB and GW.