Help- why do my Definitive Tech BP7001's sound Bad

About a year ago I purchased a brand new pair of Definitive Technology BP7001SC speakers. The problem is I am not satisfied with the sound I am getting from them. They sound good (but not mind blowing) on some recordings such as Diana Krall’s “Girl in the Other Room” and James Taylor’s “Hourglass”. They even sound good on some earlier remastered recordings like The Band’s boxed set. But for many recordings (more “rock” oriented with lots of guitars and layers of sound), Cd’s and LP’s, they sound harsh, fatiguing, and the mid range is flat and muddy. My other complaint is on many recordings the vocals sound “buried” in the mix- not as prominent as they should be. I am running them off a Denon 3805 (120 Watt per channel) receiver. This was one of the top Denon models a couple years ago (replaced by 3806 I think). Receiver was highly rated and seems to work fine. I listen to mainly music and do not yet have surround sound, so I am talking strait 2 channel stereo here. I know a lot of audiophiles say Def Techs are not great for music only but I have also read many glowing reviews of the 7001’s for music applications. I am thinking my room may be part or all of the issue. The room is full of hard surfaces- pergo floor with area rugs, sheetrock walls, not that much furniture, no drapes, etc. The dimensions are 27 x 18 feet with a 14’ high cathedral ceiling. The system is situated on one end of the 27’ wall (1 speaker near corner of room), speakers about 9 feet apart and angled slightly in. The main listening area is about 15-16 feet away (alone the opposite wall) and centered on the speakers. Actually my biggest praise for the speakers is how relatively GOOD they sound in all parts of the room. But they don’t sound that GREAT even in the prime listening spot. I have tried facing the subwoofers out vs. in and this does not seem to matter. I have also tried moving the speakers closer and further from the back wall and changing the angle, and this has not cured anything either. Right now they are about 14-16” from back wall. I currently have the speakers connected with 14 gauge speaker wire thru the “mid range/ standard” hookup method. I tired the subwoofer LFE hookup and this makes no audible diff for music. Overall, they just don’t have the WOW factor I was expecting for the price. I actually never heard them before buying. I did audition the smaller 7002 in the store and liked that so figured the 7001 would be even better. And for half price I could not pass them up.

So what do you guys think:
Are the speakers just crappy for music? (how can a 3500.00 speaker by crappy?)
Would bi-amping help the sound to any great degree?
Is the shape of my room the problem, particularly with the bi-polar config?

Any thoughts would be greatly appreciated!!