From what I've seen so far, it appears that Ginny is one of the LIs since she plays quite significant role as well as she's one of the characters that can be invited to the party (the one which the last version of the game ended with). But we both agree that occasionally having her in the bottom role would be nice.
Speaking of LIs, another obscure character is Shirley (she's the one who you meet at the bar
and later can have sex with at the pool) - from the looks she's basically a female version of Ginny, but with a much smaller role in the story. She also could be invited to the party.
It would be nice if
badvador could give us a few hints about what we can expect in the upcoming version

For now we know for sure that there will be the party scene but nothing more, like if there'll be a private club content, stuff at home, etc.