It's all about comparison. Car-sized titties are a whole lot hornier than Y-cup titties, even if a character with them looks exactly the same.
For that reason, post-universal sizes... don't work. When I have to start making up things to compare the boobs to, it stops being so good.
UNLESS the unit is also something I want to emphasize being big, in which case it works just fine. That just can't happen in this game, because nobody bigger than Yuri.
And of course, there needs to be focus. A game that tries to accommodate as many fetishes as possible is all well and good, but it'll never totally appeal to everyone. A game that knows exactly what it's doing and makes every single mechanic point towards that single goal in some way is the way to go, I think.
I'm glad you liked it, and this certainly isn't the last game I'll make.