Well IMO Bethany Hands down she was the first to see right through him.
She was strong and independent and stood by him in rough times.
Id say no to wasp because of the connection to Hank...it seems a little conflicty?
Just as an odd throwout...imagine someone like The Enchantress. Tony has helped so many other villains become heros...a little twist on the take of a Knight saving the Evil Sorceress by saving her soul and 2 people who have had their fair share of carnal pleasures finding peace with each other...and magic meets science...etc...think would make an interesting ying-yang...or maybe Morgan Le fae...etc...
Well wasp and Hank are splits these days and isn't Hank still merged with Ultron since they didn't know what else to do with them?
Pepper did vacillate between happy and tony for a time then chose Happy, but he's gone now.
Bethany, yeah she figured out he was iron Man and helped him kick the bottle the first time. Had she been around there wouldn't have been a second time. She's smart and capable despite being compromised by the controller at the moment. Also I am curious how long she has been under control. As I recall she vanished during the crossing and was not present at his rebirth party in vol three.