Seriously, is incest games still so much excite some of you guys? I was incest lover like you some time ago, pretty much focused on only one genre, but now i'm mostly just sick of it. Dev need to write a really damn good interesting story with plot twists + quality renders to actually even entice me anymore. And still, i don't really care about incest and would much prefer relationships with more distant relatives (like aunt), neighbors and "my relative's friends" category. It's situation when you eat something "new and forbidden" for days and days. It WAS fresh, delicious and exciting, but now you just eat it out of habit.
I'm not sure what do you mean by first one, but on second question, it's actually pretty common skintone in these games. Especially for MC. On third one, she's a very shy nerd a bit "out of reality". So this fashion design fits her pretty well imo.