Delightful! Love dropping by to hear his progress.

I realize he has progressed from essentially piano reductions to true piano arrangements, so this might be perceived as a step backward in some ways, but I wonder if he might enjoy experimenting with fresh arrangements of songs (or originals) for multiple instruments. GarageBand has a surprisingly high level of functionality for this, and upgrades very smoothly to Logic, which is a professional-level tool for writing and recording. I notice that he is making very nice use of voicing to pull out distinct lines, and at some point he may find himself with an inclination/need to express more timbres and textures than can be physically managed with ten fingers and one keyboard!

...pronounced like the long vowel and first letter of the alphabet...