Actually Naim electronics would pair really well with B&W. B&W is very forward sounding speakers and Naim electronics are laid back warm smooth very refined but still excel in PRAT. They will mate really well IMO. I suggest you should consider selling your Chord Dave DAC and just get the Naim Uniti Nova all-in-one integrated. I have heard this unit and is very musical sounding amp. While the Naim Uniti Nova is only rated 80 watts @ 8 ohms but it's very robust and will be able to drive most speakers.
Just my thought.