8-10k budget suggestions please

Sell the 804's and add the money to the total budget. Building something special around speakers of questionable listening qualities is bordering futile. No offense...

Come on...the syrupy and homogenized sound of McIntosh is the only thing that COULD sound good with the fatiguing and overly bright house sound of B&W. You are attempting to start fresh, so raise your listening expectations.

My first foray into high end audio had me originally lusting after a pair of B&W, they were aesthetically a good looking product with a great pedigree...it was the house monitor at Abby Road Studios, mind you. I was able to audition several models in my home paired with a McIntosh MC300, then with a borrowed Parasound. I felt every one I listened to with intent to purchase were immediately fatiguing to listen to given their very bright, in your face(in a bad way), presentation. My first pair of high(er) end speakers ended up being a pair of PSB Stratus Gold's for less than I was willing to pay for the B&W, and I was in audio nirvana...until that itch needed another scratch.

I still believe that whatever gear you decide on, the 804's will be your weak link. There are a pair of PSB Synchrony 1's on this site that would be an excellent foundation to begin your hunt for YOUR audio nirvana.

In the first 15 years of my Audio Bug, so to speak, I was completely infected by the McIntosh Brand. C42 Preamp to a C2300. MC150, MC300, MC501 Monos, MC601Monos, MC2301 Monos...the handsome looks and Big Blue Meters had me in a trance. Only when my audiophile peers within my circle of influence began venturing into brands like, Pass, Audio Research, Krell, Accuphase, Luxman, Coda etc. did I realize the the Big Mac sound that I had long coveted was not the sound that I (now)preferred. I suppose I should not speak so disparagingly of the brand because for many years as mentioned, I was as loyal as those I now question. 

I hope I am wrong for the sake of your excitement, but a Krell amp is one of the last amps I would have paired with B&W. I know most of them to be very forward and analytical, and you needed something to tame the same characteristics of your speakers. Try not to let the, "new smell"  of the amp cloud your ability to listen critically once the pairing is made...