The upgrade itch returns

We moved house and my system is now in a large living room, ceilings from 12 to 18 feet, 24x20 room open to the dining room. Big space.

I found a great deal on def tech st8080s and the bipolar design realy works well and there is still a good soundstage. Im using a Marantz 8003 cd player (and. SACD) with an Anthem AVM 30 processor as preamp and a B&K reference 2220 amp. AQ diamondbacks and granite cables.

I'm loving the sound, and yet, the upgrade itch returns--i bought the Anthem to get bass management at my old place and speakers and don't really need it with the def techs with their buit in subs. Looking for suggestions for amp or preamp upgrades. Looking for more separation, more soundstage, notwithstanding the bipolars. $2,000-$3,000, prefer used, prefer solid state.

Thanks to all.