I hope by brainwashing you mean more of the type you already did, where she becomes horny and slutty. I like it a lot more then the type where the girl becomes emotionless and just does whatever she is told. That one is just boring for me
Personally I find the horny/slutty one kinda dull. The 'sex-kitten' persona is kinda shallow, not a lot going on besides wanting to fuck all the time. Once you've seen one or two scenes like that, you've pretty much seen them all.
Seen an english H-game over on ULMF where he's doing hypnosis focusing on 'altered perceptions' focusing on women basically being oblivious.
There's some body-control where the 'hero' makes people do things that they consciousness don't want to do, but there's also stuff like a knight girl who thinks she's being 'helped into her armour' when she's actually being molested in a changing room.
Or the bandit who is convinced that aggressively riding her 'victim' is a way of 'robbing' him.
The beautiful but bored noblewoman being convinced that it's 'perfectly normal' to get fucked on her dining room table by a guy she doesn't know.
That sort of thing is more interesting, because you can do ANYTHING with it Come up with all sorts of creative ways to convince someone to sleep with you.
on the other hand, 'you want to have lots of sex' brainwashing is kind of one-note.
That seems to be what the villain-team is focusing on here though.
edit: I guess that does tie into the 'tricked' stuff you mentioned.
Usually I don't like that, because it usually seems really obvious and it's clear that the heroine should refuse if she actually dislikes that sort of thing. You've got to deliberately steer her into it, which is odd if she's in-character trying to avoid it.
Add in a little brainwashing to justify her missing the clues though, or going though it once and then accepting that 'there's nothing strange going on' so you have plenty of excuses to go back and do it again.