I think I have to tweak the hit boxes a little bit, so it's more forgiving. And probably also change from insta death so you only loose time/life when you hit an enemy.
A little more forgiving hitboxes would already help a lot. There is a lot of "I barely touched him" in there. But playing it some more, and getting it bit farther in the game, I'm already really enjoying what there is.
Edit: Finished level 3 with almost 2 minutes to spare. Would definitely play more of this. Specially levels that focus on forward momentum, like level 1.
Yes, I think for a more complex post-compo version a lot of thought has to be put into the level design to consistently push the player and give him this feeling of "Shit, I'm almost out of time" - but also with the possibility that he saves himself in the last seconds.
My mind instantly goes to a random, infinite level, turning it into a runner. But I don't want to backseat design your game. I actually really appreciated when I reached the end of level 1 and learned I don't have to keep restarting from the beginning. That was a nice surprise.