The pile height of the rug would be good information to know before ordering.  For example, if you place a rug in front of a door and the pile is too high then the door is not going to open.  I ordered a couple different rugs and the pile of one was much thicker than I was expecting, and the pile of the other was much thinner (like an outdoor rug).  It would just be helpful information to include in your rug descriptions.