Thank you so much for playing!
I am indeed planning on working on it after the jam, I have a list of design and programming fixes to make!
For your first point, I hadn't really thought about that... there is a bug that causes copies to behave incorrectly under specific conditions, which gives you less control over what can kill you I suppose... but I guess it is kind of unfair anyway if something happens to make you die off-screen, isn't it?
For the second point, I actually planned to fill in the in-level sections instead with a nice non-distracting background. I'm not an artist though and didn't have time to do that before the deadline!