Need advices to choose what heroes to farm

Hello !

I've been reading a lot, but now I'm at a point where I need advices from more experienced players ! I don't know which character to farm. I am lvl 78 (I guess 80 in 2 weeks), all of them are 77 or 78. What I have (almost all G8) :

• Rebels : Leia (7*), AA (7*),
  
• Genosians : GS (7*)
  
• Jedi : QGJ (7*), Lumi (7*)
  
• Droid : IG-86 (7*), IG-88 (6*), AK-47 (6*), B2 (5*)
  
• Ewok : Teebo (7*)
  
• First Order : Phasma (7*)
  
• Resistance : Rey (7*),
  
• Empire : RG (5*), Vader (5*)
  
• Others : Rex (5*), Daka (5*), Jawa Engineer (4*)
  

Arena team (actuallly farming them) : HK47 (L), 86, 88, B2, Engineer

Raid tam : AA (L), Leia, Phasma, Rey, QGJ. Actually farming Rex to make Teebo (L), Rex, QGJ, Phasma (or RG ?), Lumi
Now I have no idea what to farm. Should I go with Empire x5 for Potency Mods ? Scoundrels for credits ? Resistance for Speed Mods ? Jedis for Yoda ? Rebels ? Others ?
I'm not F2P, not spending much but enough to farm Rex atm and reboot some Cantina energy. I hope you guys can give me some advices :)

Thanks and have fun :)