Another pair of tower speakers is not out of the question if I can first get these bookcases in place.  We don't need thundering bass in this basement setup, so I am not committing myself to a sub yet.  It has been so long since I did any kind of due diligence on speakers that it will take me some time to decide on the right ones.  I dare not ask for any recommendations unless they are just offered voluntarily. 

  You guys are so far ahead of me on your audio knowledge.