Very cute And I really love how you pulled off so much depth with just flat tones and gradients! Have you learned any tricks and rules of thumb for that?

I wouldn't say there are any hard and fast rules for this. Just a lot of experimenting and really what it boiled down to on this project was lack of time. I had to stick with a style of toning that was quick and easy to replicate across 6 pages. Probably the biggest key is paying attention to contrast. I played with the gradients several times on each panel. Some worked, some didn't. In those cases I would use flat colors and then adjust the opacity. The ultimate goal was to make the characters pop. There's also the consideration of dramatic lighting etc. I'm no expert on it though.