Those speakers are designed to breath a bit, and so you hear some "back wall reflections" from the back drivers. So don't smuther them.
Balance width with speaker placment for bass response. They need to couple well in the room. You might have to put the bass woofers in your seat and go listen where the speakers should be. Otherwise, try different spots.
As for bi-wire, I'd tinker there last. I'd also cross em over as "small", and run a sub for best HT.
Also, those speakers do best with warmish sounding gear.
You'll have to, in short, tinker with location, and toe-in. There's no other choice.
Good luck
