How hard is the game in general?
I found it difficult, i don't play difficult games very often.
How hard is the kraken boss?
Couldn't beat it.
How hard is the crab boss?
I never got to it.
Do the controls need improvement?
as others have said the aiming becomes de-synced. wasd worked well
Game ruining aspects?
for the combat I really couldn't tell, so it seemed fine to me