Diavelet 200 and Sonus Faber Cremona

It will improve on dynamics and trebble extension but don't expect the tube quality with the human voice. You tube CD Player will help but expect a cleaner, albeit less harmonically-rich sound. It will give you more slam and scale with orchestral music for sure. It's going to be a trade off.
The right cables may help to restore harmonics and richness.
Feel free to write me if more questions.

Audio Research is an excellent match with Sonus Faber. I own Elipsa SE Reds {the baby strads} and use an Audio Research Ref 110 to drive them. The sound is exquisite. My choice for a solid state amp would probably be a Pass 30.8.

I had a Jolida 100 CD player in my system many years ago when my Theta Jade died. Granted it had the original tubes but I was not very impressed at the time. I thought the Jolida DVD player with the computer drive made a much better sounding transport. A different CD player might have a huge impact on the sound.

Would a Rogers EHF-200 be more suitable for my needs than my Mc MA2275 or the Devialet 200? Would it improve on the soft top-end without adversely affecting the warm qualities of the vocals?

It will improve on dynamics and trebble extension but don't expect the tube quality with the human voice. You tube CD Player will help but expect a cleaner, albeit less harmonically-rich sound. It will give you more slam and scale with orchestral music for sure. It's going to be a trade off.
The right cables may help to restore harmonics and richness.
Feel free to write me if more questions.

You should listen to a Devialet