Moving on from Parasound A21 (maybe?)

I'm currently using an A21 amp to power my Focal 1028 BE speakers and I don't quite feel the love anymore with my music. My system is modest, all solid state, and I'd like to keep it that way. I've been exploring stereo amps ($6K is the limit), but don't know how much of an improvement I can make. A used Pass Labs X250.8 would be ideal if it wouldn't double as a space heater (operating temp is way too high), so I'm left dabbling with the unknown. The new Bryston 4B cubed has caught my eye, but it's too new to find any critical owner reviews. I'd greatly appreciate any ideas on a possible direction to take, if any, that would musically be a step up from my A21. Beyond my Focals, my system consists of: Simaudio Moon Neo 310LP phono preamp, Avid Diva II SP TT with SME 309 tonearm, AT-ART 9 MC cartridge, Bryston BCD-3 CD player, Parasound JC 2 BP preamp, and all of my ICs are Silver Resolution from Signal Cable (XLR wherever possible).