Aw this How do you 'color' in the midtones? Fill bucket? Since you use Photoshop, why not use layers set on 'Multiply' so it doesn't effect the lovely pencil lines? Would work for everything, too. This page is fantastic, but it's a shame how adding the grey ruined the hair.
That aside, I have been enjoying the story you have shared with all of us, and look forward to seeing what happens next