There's been a moment where Z's tool somehow looked ginormous, more so than in previous scenes.... this was mostly due to perspective and angle of the panels in question... it has since been addressed.
That said, Ain's tits will probably stay the same... she's just genetically blessed in a bimbo direction.... and we've gone back and forth enough with her looks (for other reasons that can be found abundantly discussed in this thread).
Zahra also has a case of the perky boobs, so you can blame it on her genes.. most other characters are proportioned differently, so I don't think it will be too immersion breaking to have 1 or 2 outliers.
I'm a fan of games that display characters with noticeably different bodies and looks.. but that's just me. Z is the guy who decides on the look of the characters. I don't really get a vote in that (nor do I want it.. he's doing just fine and I wouldn't have it any other way)..
What I will however speak up about is that he should stick to his vision because the more popular the game becomes (and that's slowly building momentum, yay!), the more requests will pour in, often in opposite directions from one another. If he were to start listening to them, he'd end up spread too thin, and the characters would be jerked in too many different directions, both visually and conceptually.
Z has a broad plot in mind, in which we have room for a bunch of possible outcomes and developments, which we discuss and debate extensively, both the scene and the dialogue that comes with. That's what we will stick to, unless something really transcendently better comes our way... but even then, it would have to fit entirely in Z's overall mindset and view of the game.