While I wouldn't condone Byzantine iconography necessarily, I think the idea of using coloring pages is great. My wife uses stuff like this all the time and even got into hand lettering a couple of years ago, so she'll make big elaborate pages with flowing script and flowers and other little doodles in the margins. Even during church or at Bible study, if something catches her attention, rather than just taking a normal note she'll write it out in some fancy script and keep writing her regular notes around it. It probably looks chaotic to outsiders, but it works for her.