I initially was going to do it tile based, but thought it'd be cool if the shadows were coming from actual light sources instead of tiles. If I had more time, I would have adjusted the curves so the valid player movement reflects the visuals (ie the every shadow area in the game is valid. I wanted to get it so the light sources could move, or you can move into the shadow of a moving enemy as a sort of bridge.
You're completely right about the end screen, I wish I had time to just do a polish pass to add in those small little improvements.