Hoping for a little feedback on a new project. I gave my first build of this kind as a gift to a friend and now I'm finally ready to make another for myself.
Thanks to a post by LL member Savo, I found a relatively inexpensive little touchscreen with great resolution (I think the seller has a few left. Check 'em out here) and then managed to find another Philco with the perfect sized speaker grill cutout. The cabinet needs a little work, but is in pretty great condition for a 1941 antique.

What I'd love some help with is brainstorming ideas for what the 4 knobs will control.
Right now, I plan to have one power on the cpu. Another may or may not control volume, incorporating the DIY method with hacked scroll mouse outlined here, but I haven't decided whether to incorporate an amp into this project or simply have the jukebox feed an external receiver. I've always heard Windows method of lowing volume actually decreases the quality of the output, and I want as high fidelity as possible, so I may just control volume externally.
Anyway, what else could the knobs do? I'm looking for ideas that are both useful and feasible, given limited space and somewhat limited knowledge of DIY wiring.
Thanks in advance for any feedback offered.