Heroic help

Ventress is usually used in p3. She needs her unique zeta.

You should get trooper for your Resistance team.

Don't farm Jawas for any reason. You won't even need them for mods anymore pretty soon.

Drop Ugnaught hard. He doesn't have tmr. Really, just CLS and Han can solo it if you have good enough mods. Some people do the Datcha lead; I like CLS better. Either should work. I see where someone might say Qui-Gon, but he only has a percent chance at tmr--although with Dathcha it's a little better. I've found that with CLS lead, Logray works as a good third. In addition to tmr on Grievous, he can also daze the adds, so you can largely ignore them until Logray's turn comes up with just basic available. If you want to experiment with throwing Teebo in, you can. I'm sure this goes without saying, but Han needs a zeta.

But really just make sure Han and CLS are fast enough.

For p1 just gear up cls. Send him in by himself, attack, escape, repeat. You can do around 700k at a time or so playing it somewhat safe. I usually start the retreat around 8 or so before enrage just in case it fails and it will. If you get close to enrage and he hasn't escaped then forfeit and try again. You can solo p1 that way without losing a character. Two or three people doing this can clear the phase pretty quickly. Then use enough teams to get p2 down to 20% or so and then asajj, cls, bb8, and thrawn under an ackbar lead can solo the rest. Resistance does well in p2 as you said just make sure to have bb8 escape to use him later. Our guild has a one team per person to make it last longer so i usually wait for p3 to solo 2 phases for my run.

Don't find a substitute for Ugnaught. For phase 1 simply remove him completely. Only use characters with turnmeter reduction on their basic attacks. Rex works well, if you have him. Later on, when you have good gear, you can remove QGJ as well.