Thank you for replying!)
I was thinking about the point regarding in-game achievements, and I guess that would be really beneficial because it would extend the gameplay a lot. You could even add a secret, true ending after getting all the achievements (basically after getting all the other endings) which would be super cool! Maybe a little bit of 4th wall breaking would look nice as a secret ending?) Like when Kat would know that the player keeps replaying the game or something like that.
I just can't wait for the full game to come out!