Thanks! That's incredibly helpful! I tend to play Keiichi from the VNs, particularly the later arcs (and Miotsukushi-hen, which I wish had been translated), and one thing I wanted to do was strike the right balance with just how perverted he actually is and how much is for show. Of course, his character growth is something I probably would've overlooked if not for you pointing it out, though it really should be more obvious.

As for Mion, I'm probably not in as good a place to offer any advice, but you seem to have her down just fine to me so far. I'd be glad to do memes and such in the future if you want.