I'm currently top ten with a geo team. I've been using Executrix, but I'm working on Thrawn/Chimera right now and might use him when he's strong enough, not sure.
Team line up is Executrix, Sun Fac, Geo Spy, Geo Soldier with Hyena Bomber, Hounds Tooth and Asohka Tano on support (although I'm going to change her out for Vulture Droid when's high enough). I bring out Hyena Bomber first for the crit reduction and buffs, and tank. Then hounds tooth or Ahsoka depending if I need another tank or I need to chew up some buffs on the enemy team.
My Geo's currently murder strong Hounds Tooth teams and my Geo soldier is fully spliced.
Check out my profile https://swgoh.gg/p/348917497/
I'm currently in 10th and I think I'll be able to beat that today.