Thanks for the feedback, I like your idea of speeding up the game with shift, I also agree the first zone is a bit boring for replaying the game, but its necessary for first playthroughs so your solution solves the problem!
And yeah, the color mixing guide on the left can be improved a lot. Its a thing I made last day for people that were forgetting the controls. I thought about the typical color circles combinations in art class, but with my controls another type of graph would better fit in. But as you said, purple is the hardest to show (and to shoot).