Need upgrade, sell the B&W 602 and get a tube amp?

Focus on the amplification more than the speakers. If you borrow a better amp to try, you will find those B&W sound better than you think. If you're using cheap cables and wires, replace them also.

If you listen to music more that watch movies, sell the Denon and get a Rogue Tempest Magnum Integrated. The 602's are good speakers for a fair size room. Also, what is your source?

The source: Panasonic 91- nice unit with separate outs for music audio. Using OK connects and 12ga stranded speaker wire.

Look into a mellow/smooth interconnect.(Van den Hul D-102 III.) Also, if the 2802 has metal jumpers from pre to main in, consider replacing those also w/VDH. Will tame the harshness. Also, find a "Straightwire" retailer. Try out some Quartet spk. wire. They would probably loan you a set
to try out. Excellent wire at a very affordable price. If that doesn't do it, consider a spk. or amplification change.
IMHO, I don't think you'll go wrong with the VDH interconnects and you can most likely try out the spk. wire
on a loaner basis. Hope things work out. Bill

With 2K you could do tonnes of good things with this system. I'm not sure what your priorities are when it comes to 2 channel vs HT percentages, but I can only say that money spent on some good cables like some Virtual Dynamics Audition speaker and IC's will make a world of difference. But before before upgrading cables and revealing the nasties, please upgrade the Amp and source. Your problems will be solved with some half decent tube amps like the Rogue 88's which can be had for $800 on Audiogon sometimes. Please let us know what you do most with your system, or what kind of sound you'd like to get out of your upgrades.