Very well polished game, obviously. Top marks there.
On theme and gameplay:
I would say it does not feel to me like "failure is progress", because when I'm in walking mode I see the enemies as powerups rather than "fail state"; only when I'm in flying mode do I see enemies as "fail states".
The strategy in this game is - throw myself into an enemy to get to the end of the level fast; to make it interesting you need to have bits where throwing yourself into the enemy is not the optimal choice. You have that at the bit where you need to wait for the enemy to get close to the wall so you can blow it up; but it's frustrating having to wait.