The jump felt unsatisfying to me. Perhaps I'm expecting letting go of forward to decelerate my velocity.
You need to pass a certain velocity threshold to get on a barrel which is pretty slim. too low and you slide off, too high and you fall. I think the collision is slippery and weird.
Hammers might be too fast for a first trap thing, It's the start of the level so I don't think the window should be that slim, yet.
I like the graphics and sounds(sounds could be improved)
Disclaimer: I played for 5 minutes due to not liking the jump physics.