A significant number of Old English Game Bantam breeders will do just that. It really helps with strong wings and wing carriage and good firm breast development. I've done it with all manner of fowl, really almost prefer it to stationary.
As far as other questions in OP, for height it would depend on breed, I keep most of my bantam perches 3' - 5' off ground. Use either 3/4" or 1" diameter PVC pipe as a deterrent to creepy crawlies like mites and lice. Run size is really a matter of preference. Bantam breeds can usually fly pretty well and are more susceptible to air borne predators, so I'd say the biggest you can cover. Anywhere from 5-7 sqft per bird is plenty (coop/run combined, for example I have a 4'x8' covered pen that I'm using for housing for 6 Old English Game Bantams, it works pretty well)