I currently have a 6.1 loft setup using Klipsch xb-10 bookshelf speakers I got a few years ago on clearance for all 6 channels. I believe they were part of the icon series at the time. One of these is currently laid sideways as a centre channel. The room is an approx 10’x 20’ narrow loft setup. I have a Yamaha aventage receiver and a Klipsch R-10sw sub. Any advice on what centre channel might improve the setup? I thought the regular Best Buy R-25c centre speaker might not be much of an upgrade. Also, if I were to keep three of these Xb-10’s as my rear surrounds, what wall-mounted speakers might be an upgrade for my front left and right channels? Thanks!