Thanks for the constructive suggestion! I actually went so far toward keyboard implementation as to detect the holding/release of the various keys, though I eventually weighed against connecting them to character movement for two reasons:
1- This is a port of an app I originally made for iPad and iPhone touch screens. It was designed with locational input in mind, and I worried whether platformer directional controls might trivialize the few jump puzzles.
2- I like that clicking the right side of each screen to advance feels a bit conceptually like turning the page in a (the!) book. I may be overplaying the importance of this aspect in my imagination, but I was on the lookout throughout development to keep it connected to its textual (as opposed to experiential) basis, the text itself being a known deviation/exaggeration of Thoreau's true experiences.
Thank you especially for not being harsh about audience mismatch. I struggle to find the right places to put the sort of things I make, since they're generally not games, yet they fit easiest and find the largest audiences within virtual spaces for hosting games. (Newgrounds seems a better community fit by far compared to Kongregate. For this particular project, at least.)