Hi there, thank you for your comments! :)
We definitely agree that there's several parts in need of some heavy polishing (especially towards the end).
The puzzle aspect of our game is quite light since Project Kat is meant to double as a prologue, so the difficulty is of a tutorial-level. That said, the full game will concentrate more on the different choices you can make. Due to this, the difficulty in the puzzles might come from trying to find one specific solution (for example: finding out if you can befriend the three girls), while finding any solution at all should prove to be quite simple. We will however do our best to create a comfortable difficulty curve as the story progresses. It's obviously not fun if it's too easy (but it's not fun to get stuck either)!
As for your second point, you have some interesting ideas! That part of the game is a little wonky and we plan to fix several details for when we release the full game (as well as add choices and endings) , hopefully it will flow better once we change it.
Thank you for the constructive criticism! We'll do our best to turn your 6/10 into a 9/10 ;) Hope you'll play the full version!