Your system looks great, it's where I'd hope to be someday.
I bet it sounds great with that equipment and room treatments.
How do you like that Audio Research preamp? I've had some experience with some of their older models and am a fan.
I've found with the Monitor Audio's, they give lots of details and have very good extension in frequency. If anything, they seem to like warm electronics. Bet they sound great with your tube amp.