Which ones do you guys recommend most? Only tried HS tutor yet and liking it.
As
eric_alvin said, Lessons in Love has become pretty popular (I haven't played it yet). Corrupted Kingdoms is probably the most popular game, definitely not the best Koikatu game IMO but it's worth the mention. If you like femdom (soft femdom as far as I know) Android's Life is a Koikatu game where the dev draws over the CGs giving a wonderfull result that you won't find in any other Koikatu game. Allow me to shamefully self-promote my own game Complex Society, because why not? Harem Highschool, even if it's abandoned, it's one of the first Koikatu games and still one of the best games IMO. Long Lost Daughter gives you a harem and a deep and emotional story at the same time that you can skip if you just want the harem. I haven't played Hero's Harem Guild yet but it's another game that become absurdly popular like Lessons in Love.
I haven't played all games listed in the OP so I'm definitely missing good games, but if you ask me where to start, those 7 games are more than enough to keep you busy some time.
Edit: I didn't recommend HS Tutor because you already played it, but that's my favorite game in this site. I recommend you Solvalley School from the same dev but it's done with Honey Select.