My issue with the bosses was a lot of them were just floating hitboxes way above the player which boiled those fight down to jump under the boss to spam up attack. I also didn't enjoy that pretty much every boss had an AOE attack that (at least as much as I tried) you couldn't counter which ended up just prolonging those fights.
And now that you mention it I also felt like some enemy placement and platforming hazards were there just to waste your time.