Great first game! I agree with the other comments, being able to look around would be a huge improvement.
One note on the movement: when you are moving diagonally then jump then land while holding W, your character continues to slide a bit in the original left/right direction. If you jump diagonally then land while not holding any movement keys, however, you stop instantly. Not a huge deal, but I think that might be contributing to what people are describing as the movement feeling odd.