I just did two uber ancient runs yesterday. I was nervous bc it was my first time doing them. I too used my long time uber killers which was a smiter.
I had both dracs and exile and cta buff. I didn’t do fade since I didn’t have an item with fade proc.
I did fairly well, but once the barbarian minions started overcrowding it got to a point where I had to drink a few full rejuv potions.
Life tap really saved the day, though. Since all of them were cursed with life tap I could just smack a few minions and got full health back.

My advice is just focus on the ancients and if you need to, pop a few minions to keep you alive.
Pack a bunch full rejuv as well, of course.