Amp for pioneer
I don't think the pre-amp stage of your pioneer is worthy of a $1500 amp. You should consider a pro-amp like the $180 Behrenger A500 to drive the mains. Spend the rest on a new sub, DVD player, speaker upgrade, room treatments, etc.
If you are set on spending $1500 on an amp, consider getting the Emotiva MPS1 with 3 channels. You can add additional mono or stereo amps down the road in the 4 remaining slots.