Integrated Amp Upgrade Advice?

I have a Yamaha A-S501 integrated amp paired with B&W 607 S2 Anniversary Edition bookshelf speakers. I'm seeing to upgrade the amp to at least a 100W one as the 501 is 85W.

My potential upgrades consist of a Marantz Model 30, a Parasound Halo Hint 6 or a pre+power combo of the Rotel RC-1590 MKII & Rotel RB-1552 MKII.

If anyone has any experience with the above amps (or one in a similar $3000-$4000 price range) with Bower & Wilkins speakers, which of them would be the best pairing?

Location: New York City

Distance to speakers: Approximately 6-7 feet

Room size: 135 square feet (10 ft length x 13.5 width)