I Feel Bad For You
It's obvious you put a lot of work into this game, but you failed at creating a fun engine. That alone will cause this game to go from a potential 4.3+ to a lousy 3.6. Unfortunately there's not much you can do now that the game is released though.
Biggest mistakes I saw immediately:
Movements and Stab engine simply were not fun
Extremely long introduction before you got to play the game
No Checkpoints throughout a level, you had to start from the very beginning
Don't let this discourage you from making large games in the future, just make sure with the next one you make that you focus on the core game play mechanic before you make a large amount of content around it. I would suggest making a lot of small games to experiment before you go making something on this scale again.