Here's how I would approach your situation:
1. As others have already suggested, re-position your front L/R speakers in from room corners. Tilt the front of the center channel up towards LP.
2. Get new AVR for newer CODECS/connectivity/Audyssey MultiEQ XT32Denon AVR-X4000 - $1299
3. Get new powerful subwoofer (duals would be even better). Rythmik or other favored brand (e.g.Hsu, SVS, Power Sound Audio -- NOT Epik at this time).
What is the actual physical size of your room (not just to your LP)?
If getting dual subs:
2ea. Rythmik LV-12
- $1180 (this would be my choice)
2ea. Hsu VTF-2 MK4
2ea. SVS SB12-NSD
If getting only one sub:
4. Your current speakers aren't dogs so I would totally re-evaluate the system's SQ after dialing in the speakers/subs with Audyssey XT32, I would bet that a properly calibrated system will surprise you...but if you really want a new set, go for it.
Recommend purchasing front ported speakers so that they can be placed closer to corners/walls if needed.
Since you prefer not to purchase speakers you can't listen to, you still don't have to limit yourself to what Best Buy carries.
Crutchfield offers 60 day satifaction guarantee (you have to pay some return shipping on the towers). Prices are usually MSRP but they have a great reputation for service.
Here's a couple of front ported possibilities from Crutchfield:Focal Chorus 726
- $925 each = $1850 pairFocal Chorus CC700
- $650Focal Chorus 706
- $750 pair
Substitute Chorus 716
instead of 726 = $2950
orPSB Image T6
- $650 each = $1300 pairPSB Image C5
- $400PSB Image B6
- $550 pair
Any of the other speakers that the others have recommended (those JBL LS40's look pretty sweet).
5. If you still feel that the AVR is struggling to drive the speakers, get a power amp to assist the AVR.
Get a 3 Channel amp for L/C/R, then drive the surrounds with the AVR.Emotiva XPA-3
It's always fun spending someone else's money - happy hunting.