Helena prediction
I think Helena was genuinely starting to enjoy being an innie. Contrary to the opinion that she planned it out the whole time just to get in Mark's pants and play the long game, I think sleeping with Mark was an impulsive decision essentially made on the fly and she just went with the moment.
I get the feeling she had no experience with being in a relationship, and was very intrigued watching the footage of Mark and Helly interact because they had a dynamic she's never experienced—genuine friendship and love. As Helena, she's had to be the perfect Eagan puppet and be "on" all the time so pretending to be an innie is a break for her, it may have started out as just what she had to do to keep the cover up but she actually became attracted to Mark. All signs point to Helena having a very cloistered existence.
This episode she was poking fun at the absurdity of Eagan lore, I didn't get the feeling that she was just doing what she thought Helly would've done to fit in with the group, she was actually letting loose. Her saying she didn’t like who she was on the outside was also the first hint of honesty we've seen from her.
Hot take: I think at some point either by the end of this season or next Helena will start to turn and realize even with the power she has, she has been just as trapped as the innies, just in a different way.