So at this point I'm putting a temporary halt to scanning more scenes, as they may need to be re-scanned at greyscale rather than black & white. I'm also toying with the idea of possibly shading in each drawing with colored pencil, for a totally different look altogether. Since the story is being read from a childrens' book, it might be cool if the whole thing looked more hand-crafted. I'm going to do an experiment with both methods (digital ink-paint vs. colored pencil) and see which one looks best.
Not quite as sketchy as this...
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...but something close to it.