I just wanted to add a few more suggestions of ways to develop the 'skeleton'
Try adding multiple voices maybe in the left hand (think RH of moonlight sonata mvt. 1) - this maybe difficult due to the range of movement but might be worth considering
Try incorporating/imitating another style - either a genre or a composer
Try swapping around the hands - having the arpeggiated movement in the RH, higher up etc
Try using different tempos (tempi?) and/or different dynamics - neither of these change throughout, adding a rit or accel, or a faster/slower section would provide some contrast (similar things for the dynamics)
Overall, just experiment, maybe play it through on a piano a few times and see what works. If you do change it, I'd like to see the new product