Finally got to play a bit with 1.1 and the mods re-added.
Gameplay changes that I noted so far:
1: you can run around the map and "gather" different "topics" that you can use when you talk to a girl. This replaces the "3 answer question" from KK1 and is definitely an improvement.
2: You are not being "punished" anymore for giving a wrong answer, your "favor" (the heart gauge) wont go down anymore, it just wont increase either - definitely an improvement given that the game supports up to 100 girls, if I have seen things correctly. (default is 40)
3: Map locations are a lot more diverse now, its not "4 different classroms + courtyard" anymore, this is a massive improvement over the previous game in my opinion.
4: Interactions with Girls give "koiktasu points" that you can exchange for money, which you (probably, didnt try yet) can use to buy stuff in the store.
5: Obviously, we do get the "massage option" from Sexy Beach in this game. (Would consider this a "win" over KK1 too.)
I didnt get to try fukky fukky yet, due to there being a lot of talky talky (fukky-positions are not unlocked in Free H, so you actually have to play the game for once.), but so far, it really looks like an improvement, even the performance is good.
Overall, this game heavily reminds me of Artificial Girl 3 over anything else, simply because it had similar gameplay/maps and so on, I would consider this "AG4" over AIS, but for the ones who want AA3... dont get your hopes up, it isnt.
That said, one can already see where future areas for DLCs are supposed to be, they are just "locked behind fences" (the entries).