center channel upgrade question

[buckshot]

I have been upgrading my home theater set up in pieces (essentially what's on sale at frys) and have hit a problem. I now have balboa 30 front floor standing speakers from jbl, the side channels are the old front channels from my onkyo theater in a box, and the rear channels are polk audio R300 floor standing speakers. I am not a huge audiophile so this set up is pretty good for me. I got a 10'' 150W velodyne sub as well. the problem is my center channel is from that onkyo set and is sounding pretty thin. I turned up the level for that speaker to quick fix it. but am getting more annoyed with it. i'm looking for a good center channel to go along with what I have now. price does matter a lot. i'm hoping to get away with a sub $250 amount. I can hunt for deals but I need to know what to look for first.

any help is appreciated. thanks.