I think the idea is wonderful. I am wondering, though, if diversity is a goal in the comic. Captain Encouragement is Caucasian, as is the only other person pictured on the first comic book.
I saw your idea and immediately thought of how many different populations I've worked with that would benefit from it...but I work really hard not to teach with materials that don't include images of those I am teaching...Can I help with ideas in any way?