I like poppa's suggestion of a used Bellari. In addition to that, I'd offer up the idea of a tube buffer. Grant sells one for $125. That would give you a bit of the tube experience.

The thing with tube gear, though, is it seems to me you have to be willing to spend some bucks on it. Perhaps it's different with vintage gear...poppachubby could comment more on that than I could. But with the new tube gear I've heard and/or researched it seems like the lower end of the price range sounds too tubey. It can be fun to listen to but it makes compromises that might not be acceptable.

As for MC cartridges, keep an eye on compliance and mass when you're shopping for these. I see you didn't mention the Denon DL-103, so maybe you're already doing that. One thing you could consider is something like Bellari and a Goldring 1042 cartridge. The 1042's output would be high enough to work very comfortably with the Bellari. The 1042 seems to me to provide that elusive combination of detail and warmth.

I need to go back and look at what gear you have, though. What's your current phono stage?