A clip on food tray might be a worthwhile addition. Snack while you (don't) exercise. That motor looks newer than the unit. Is it a replacement? I cannot believe anyone would wear one of those out.
I think the paint shaker suggestion is a good one. Even if just for rattle cans. I mentioned shaking spray cans to my HD rep last time I bought spray paint and he said he thought that was a great idea. Evidently they get inserts from the "shaker" manufacturer for quarts and pints. He was gonna suggest they come up with an insert to carry four rattle cans.