I think the NHT's are a very good match with the Rotel. And the NHT's dont really lack high frequency, its just that they are not as bright as the B&W's. I found the treble in the NHT's very smooth and maybe just a little rolled off compared to the 685's. The store that I listened to the NHT's sold Paradigm speakers, and Rotel, jolida, Integra, Parasound, and Anthem amps. They had the NHT's paired with the Rotels, Integra and jolida amps.

Give the NHT's a listen, you can pick up the Classic 3's for $650.