This is simple yet effective and I'm so glad there are more people out there doing shared keyboard multiplayer games. You also managed to make the levels interesting, good job :)
Edit: I just tried it with my partner, we had a blast!
I'm so glad you like it! It'd be fun to add more co op input options, but for this game jam I thought it'd be best to keep it simple. .
...in the other direction, I wonder how many players I could add to one keyboard.