I need tips to improve my setup.

Equipments
AVR : http://www.yamaha.ca/av/Receivers/RX_V650Ti.jsp
Front: 2xM22TI
Back: axiom ax1.5
Center: old axiom center(vp100??)
sub : PSB 12"

http://www.woxxom.com/images/front.jpg
http://www.woxxom.com/images/back.jpg


I'm open to suggestions..