I assume you're not happy with the sound, but you don't comment on why you asking for help, specifically what kind of advise you are seeking.
That said, you might try placing your speakers closer to the side walls so the drivers are about 10 1/2 ft apart to give you something closer to a triangle. Should give you a wider sound stage. You will probably want to re-visit toe in after you do that to smooth out the highs. Cardas is a great starting point but it's just that, a starting point.
Have you taken care to treat (with furniture, rugs, etc) the first reflection points?
That said, you might try placing your speakers closer to the side walls so the drivers are about 10 1/2 ft apart to give you something closer to a triangle. Should give you a wider sound stage. You will probably want to re-visit toe in after you do that to smooth out the highs. Cardas is a great starting point but it's just that, a starting point.
Have you taken care to treat (with furniture, rugs, etc) the first reflection points?