I feel like this is a silly question, but what color layers exist in typical C-41 film and in what order do they develop? If I develop longer, which colors end up developing more first?
Look at the chart page 5-30 of the Kodak Z-131 processing manual. It's pretty cool showing the effect of developing time on the colors/layers. There are charts for variance of other parameters like temperature & agitation.
If you have access to a University Library you should be able to electronically download David Rogers 2007 book, "The Chemistry of Photography, From Classical to Digital Technologies". Basic colour coverage of layers, chemistry, etc.
ISBN-10: 0-95404-273-3