Upgrade advice for processor

Since you mention that HDMI is not a necessity, I would consider a used Meridian G68. I am very happy with mine for both movies and 2 channel.

Since you mentioned that 2 channel sound quality is a priority for you, and you are leaning toward Anthem, I would consider getting the Anthem Statement A5 rather than the MCA-50, if you can stretch the budget slightly. I have the A5 and I can tell you that it performs quite nicely on both movies and music (though it is not my current music amp).

I am under the impression that the A5 uses a variety of upgraded parts. I could be wrong about that. You should consult your Anthem dealer.

No, I did not listen to both amps. My advice was not based on any negative experience with the MCA-50. It was based on my highly positive experience with the A5. I used the A5 for both music and movies for two years. It is an excellent product at what is, by audiophile standards, a very reasonable price. You can click on my virtual system to get an idea of the system context in which I evaluated the A5.

I have also heard the D2 on a number of occasions (combined with the P5, which, although it is more powerful, sounds very similar to the A5). So I can make a reasonable inference about how the D2 and A5 will sound together. I believe that combination will meet or exceed your expectation, as described in the OP, of "high quality 2 channel performance" from a multichannel processor/amp. Good luck.