What would improve the soundstage of my B&W 802s3

Just purchased B&W Matrix 802s3. Upgraded from Polk Monitor10-B. Driving with B&K EX-442 200 wpc, dual mono, And Audio Research LS-7 tubed preamp. Audioquest Indigo speaker cable and AQ Ruby interconnect from pre to amp. Would it be better to go to monoblocks i.e. B&K M200's or a better amp like Mark Levinson or Classe' Or Better cable? Maybe even a tubed amp. I dont know much about bi amping. Tried bi wiring but no big difference. These speakers do double duty as home theater speakers, I unplug the bananas from the 2 channel system and plug in the bananas from the surround system for movies, so bi wiring is kind of out of the question right now. I'd really like to get more depth in the sound stage although placement of voice and instrumentation are very good, though limited to between the speakers. Any thoughts would be appreciated.