I would not put more than one fish in a ten gallon. It will create too much strain on the biofiltration and your tank would be teetering on the verge of an algae outbreak constantly if you were to ever get it under control.
Furthermore, why would you do that to an animal? There would be practially NO area to swim if you had the proper amounts of live rock in there, regardless of how many hiding places they have.
Stick with one fish. If you MUST have more than one, go with the tiny little inch long gobies.