To add to what Paragus is saying...
I think your game needs a lot of room changes, especially with troll traps and add more "real" platforming.
You need more saves.
Less "Facepalm" moments where the player just wants to ragequit.
Better places to use special mechanics.
A PROGRESSIVE change to the difficulty of the levels and bosses. I specify the fact that it should be progressive as the player gets further in the level. Don't put a random shitfest in the middle of a level.
Some bosses need to have their HP reduced by A LOT. Or think of a way to have the boss take more damage while having the player NOT spam the button.
That's all I can think of right now, but there is a LOT more that can be said.