I finally found time to play the whole game from the scratch and to unlock everything.
Unfortunately, the walktrough isn't 100% correct. Some parts are missing (i.e. Heather's masturbation scene/the renders during Isabella's free roam after you choose her). Also it should point out the branching a bit more specific (i.e. the fact that you have to tell Lily at the party that you would like to have a personal stripper to get the sex scene with her). Plus there is one clear mistake as it tells you that there is a special render in Isabella's living room somewhere around the table, which clearly isn't there.
If it wasn't for the first sex scene with Maya in Episode 1, the game could be played completely with only DIK oder CHICK choices in two runs, I guess (one DIK, one CHICK). Exception is the part where you have to choose where to stay at night. Because of the flaws of the walkthrough and that Maya scene, I managed to unlock everything but four scenes in the end, so I had to replay some parts of the game, but that's ok in my opinion.
I never got that deep into the story before and I only played the CHICK path. Now that I have played everthing, I guess the CHICK path is the one that must be the real story. The DIK path is simply fucking everything and seems to only leave possibilitys with Jill and Sage for future relationships (if nothing big happens). The CHICK path opens doors to all the girls (Isabella, Jill, Maya, Josy, Sage).
I'm fairly interested in the past relationship between Isabella and Jill, especially after the last night at Isabella's house.
My favourite girl is Heather btw. I hope she plays a bigger role in future updates. I also like Elena. Those two definately had not enough screen time.