Thanks! Coming of age / found family hits the nail on the head. According to one site, it's at 800+ pages right now. I'm pretty sure that's going to impact prices a bit if I do decide to make a physical copy. 
A 140-page comic?? Huge congrats! I'm a week away from the five-year mark, myself! It's definitely longer than I wanted to take, but maybe the sixth year will be the charm, fingers crossed. Burnout isn't as much of a problem for me as time management. Did you ever struggle with that when it came to your comic, and if so, how did you handle it?
Oh, this is interesting! I can definitely see that happening, figuring out more impactful plot and character beats along the way. Your plotting process sounds a lot like mine. No matter how much I try to plan things out, the characters tend to have other plans, so I've learned to keep it loose.
Do you know of any publishers who print novels with full color illustrations? I've only seen novels with greyscale pictures. I wouldn't mind doing that (or no pictures at all if the prices came down to it) but I feel like colors are my strength.
