Functionally, I went with bare bottom with just a cosmetic <1/2 inch layer of sand, easy to keep clean, no sand blowing around, no nutrient sink. Snails could travel around easily, on the glass bottom.
I also kept (Florida crush coral #5) a gravel bed in my sump for ricordea farming and I found that some of my fish, (I started keeping gobies and dragonettes), were growing fat in the sump, but not in the main display. I found that copepods and amphipods can colonize a gravel bed, so now I have a half inch of sand/gravel in the main tank.