Might I also posit SRP in place of STHan, especially now that he's easily farmable? Don't kill me, hear me out.
Bistan's special removes TM according to his potency, and his potency is +10% for each buffed ally and each debuffed enemy, and SRP has an AoE Offense Down when he taunts. This boosts Bistan's potency up to 50%.
Han's utility is really in his TM stuff; he doesn't have as much health or defense maxed as newer tanks, SRP included. His TM removal is only 25% chance maxed, and while the group gain on the special for Bistan doesn't quite make up for STH, and the gain for damage is gone, keep in mind that SRP gives everyone +15% TM with his basic. So, not quite what STH gives for taking damage...but SRP also gives all others Speed Up for two turns when he dies, and then can revive with half his health. When STH taunts and gets piled on and dies, no more TM effects.
So, taking out STH will lose you some TM stuff, but it seems like the Bistan/SRP combo would give you more overall. You might lose some damage from Han's blaster, but if you're running Wiggs or Landeia (Leiando?), you could make up for it.
Oh, please don't pile on me for suggesting that Leia might have some utility. Properly modded, she can deal a lot of damage. She also can grant everyone crit chance up, which not only adds to their damage, but also to Bistan's potency.
I think the real problem here is that there ARE too many rebels. If there were an epic battle mode, where you could do 10 on 10 teams, I think rebels would dominate.
Anyway, perfectly willing to listen to debate on this. Discuss.