I've been finishing up the current submission, and one of the things I've been doing is muting the colors a little. I found that in the original format my comic looked a little too kiddie. I'm trying to write an all-ages comic, but not a comic specifically targeted at the youngest of the young kids.
The original version just looked a little too crayola-bright, so I muted the colors by desaturating them a little. I'm not great with colors, so it took a while and I'm not 100% stoked about the results, but it looks better, at least. The original is on the left, and the yellow-green-blue combo was just too bright for my tastes.
(click image to enlarge)