Keep your speaker cables the same length. I have been faced with the same dilema, so what I have done is to coil the excess cable behind my rack. One option that I have been considering for a while is to purchase an AV table/rack to place in front of my RPTV. This would give me center massed storage and a stand for my center channel. If height is an issue for this solution you could have a solid riser built for your RPTV with a tunnel through the center to run cables through.
Just some thoughts.
Just some thoughts.