Right Handed Piano Techniques

I am currently writing a Right Handed Piano Toccata, for a pianist who broke his left arm, but played a competition with it anyway. Although much literature is available for the left hand, very little is extant, so I am writing him something to play until he heals. It's been going pretty smoothly, with a G minor/phrygian area containing the main themes, based on a repeated note motif, and a transition opportunity to an Ab second theme area.

I have been working on this by writing while sitting on my left hand. The main challenge has been creating a variety of texture. At first I basically had just chords and lines, mixed together. Voice leading was intact but uninspiring, do to the limited range.
My breakthrough came when I tried adding in arpeggiation patterns. I reached the conclusion that any combination of notes that can be hit simultaneously can be hit in any order at any speed. This quickly opened up the piece from sterile part-writing into a dynamic,evocative soundscape, while still retaining the architectural integrity. (At least, that's what I hope).

As a new member of this website, I'm curious what other composers would think about this challenge, of creating variety in range, texture, and mood with only one hand. (I am restricting the one hand to a span of an octave, for the purposes of being playable by my students). Any thoughts or comments are appreciated.