Would love to see the different love interests find love outside of mei. Karin seems like poly-ish kind of person but that might be related to a lack of faith that any relationships can work. Mei doesn't like the poly stuff so I can see karin ending up with one of the other girls.
Also the competitive ones may find that their competitive natures is something they can admire about each other. Could open up the chance for them to build friendly relations that could lead to something more.
Prof is kinda screwed rn though. She got no one other than mei and mei doesn't seem capable of choosing anyone. Plus that relationship can ruin prof's reputation and maybe even career. "I heard prof looks at her female students with lustful intentions." "Wow I never took her for a creepy type but I guess you never know." Something like that.
Poor prof. Someone give her a chance at love too