If you’re really thinking of upgrading speakers in the not-too-distant future, I’d look to narrow down what those might be as the amp you buy now may not be a good match for those. That aside, as you seem to prefer a more neutral kind of sound, I’d recommend a used Hegel H160. It’s a great all-around amp (you can read the reviews) and has enough power to get the most out of your CM9s, and there’s one available on US Audio Mart for $1900. Hope this helps, and best of luck.
2 channel amp suggestion
I've had mostly NAD gear for quite a while, starting with a 3020 years ago...a while back my OLD C270 amp started losing it in the right channel so I am using the Front speaker wires on my NAD 758 rather than Preamp outs and an amp while I research a replacement...my stereo music sources are an Oppo 103, Bluseound Node2 with HiRes Tidal account, and a Project Expression 3..but only with the Sumiko Oyster...(next upgrade?)...I have B&W CM9s with a Velodyne subwoofer filling the really low end in an oddly shaped living room...I see the 275BEE is the NAD replacement but the stores I have nearby have Atoll, Anthem and Rotel in that 2 "grandish" or less price range...any suggestions? Perhaps the Used market? Thanks...love this Forum...