1) Sounds good but please don't bite off more than you can chew... The more the story branches the more you need to develop, etc.
2) I am glad that every woman will be optional. However it would be refreshing if their entire branch/story was optional. Why should the MC waste his time being Vanessa's "assistant"? I know you have a story idea but allowing the player to shut down that entire branch (their loss if they don't want to experience it) would be different and appreciated. I don't care about learning anything about Vanessa and only am interested in finding out if Riley can help Billy Love stay open (IMO she can't, she's an intern).
3) The issue with Vanessa and the assistant situation is that it was just a bad reason for the MC to get to know her. The Dean of Psychology (who shouldn't have a job if there is only 1 student finishing their psychology degree) gives Vanessa the MC's number to have her help him and instead he is roped into being a free "assistant" for her. That makes no sense... The MC should be able to tell Vanessa to fuck off, they aren't in a small town, he should be able to find other people to do personality profiles. He could advertise in the coffee shop and interview people there. He doesn't need Vanessa. And accepting a subservient position with her that has no end date or described duties is
. I hope the second episode isn't overly Vanessa heavy.
4) That's fine but it isn't very well thought out. The MC should be able to get personality profiles from students or coffee shop customers, he shouldn't need to wander Old Town at night or become a bitchy woman's unpaid servant. He could even advertise on social media that he is looking for people to interview for his thesis. I'd suggest adding a cute, shy, "innocent" shut in student who would answer his ad since the MC shouldn't use himself as the subject of his thesis.
Don't feel like you have to include lewd scenes in each episode, tell your story and let those moments be more natural. The blowjob with Erika felt like it was there as a way to ensure there was some lewdness, unless it turns out that she's just a slut and will do anyone.
There are a lot of college/school setting games, don't force yourself to be "unique" but try to avoid the overused tropes and cliches if you don't want to get lost in the flood (in the last 48 hours I've seen at least 3 new school setting/male protagonist/Renpy-VN games appear on F95).