Denon 3806 + B&W 803D....amp suggestions???

Hey All,

I've got an uncle with a dilemma. He's currently got his 3806 already running his house system (speakers on the back porch, speakers in the kitchen, etc) in addition to his mains 803D's. His primary area where he seeks to invest is the main listening room where he desires high quality 2 channel stereo performance, though he knows his in-wall b&w's will respond favorably to more amplification. If possible, he desires to keep the 3806 and just use it for it's processing capabilities expanding his amplification or just keep life simple by buying yet a more powerful receiver. He just got the 803D's and he understands that the 3806 is not adequate...he just needs suggestions.

Listening preferences: stringed instruments, jazz, female vocalists, some orchestra

Main listening room:
25x20 however room has 20 foot ceiling that opens to second floor

Main speakers: B&W 803D.

Amplification: Denon 3806 plus ?

7 channel amplification (or a 5 channel plus a 2 channel) or replacing the Denon 3806 with a more powerful receiver? Which route and what are some recommendations for components?

Thanks,
Justin