You can customize the controls by pressing F1 > Settings. (I can tell my control schemes are just my preferences which are not for everyone, and tried to make it so its possible to play "one-handed" lol)
To be honest, combat and jumping could be better, but I liked how it feels, guess I got used to it during the development and didn't improve them more than that.
Also, sorry if you found bugs during your gameplay. Maybe I should update the demo since I fixed many bugs in the complete game. That softlock should not happen.
Oh and thanks for sharing your honest impression, I'm paying more attention in the game feeling for future games.