JB_PT I have an acoustic and it's on caster cups. My pedals are 3 inches from the floor.
I have my digital cabinet on shock absorvers (one inch higher) to dampen impact sound, so the people living the floor under me won't hear anymore my playing noise. This little extra inch was already very uncomfortable for me to pedal. I solved it by attaching a door-mat to a wooden board (60x40cm) under the pedals to have my feet at pedal level again. This works quite well.
And this brings me to another thing I was thinking for quite a while: About height of the keyboard of acoustics and digital cabinets. It seems there is a standard height, isn't it? And this standard was established a long time ago when people where smaller on average. For big people nowadays, the keyboard height could be too low from an ergonomic perspective. Ok, with casters the entire piano can be lifted completely, but then the pedals are lifted off the ground, too. And this makes it uncomfortable to play. AFAIK some companies like Bรถsendorfer offers modification kits to extend the length of the lyra (don't know the english word for the housing for the rods to the pedals). And indeed I can imagine for a grand piano, this work very well. But what about uprights? Is there a way to extend the keyboard-pedal distance at all?