I need help choosing my next tube preamp.

Although I really enjoyed usnig my ARC LS-15 preamp since I bought it brand new several years ago, I'm looking to upgrade it.

I'd like to stay with tube preamps only.

I like experimenting with different tubes, so the new preamp should probably not be based on the new 6H30 supertube.

Qualities I'm looking for in my next preamp - it should have a pretty laid back(more so than the LS-15) but dynamic character, with plenty of detail, but not be hyper detailed, should have good definition in the bass region(deep, tight bass, not bloaty), full sounding mids and produce a wide and deep soundstage.
Also, it should have a high resolution volume control with plenty of steps to provide ability to fine tune volume for late night low-level listening.

Primary source in my system is digital. No analog as of yet.

The candidate preamps are:
ARC LS-25 MkI,
BAT VK-31,
Sonic Frontiers Line-3
Aesthetix Calypso

I'm pretty much open to other tube preamp suggestions, as long as it is from a well known manufacturer and is not known to have reliability issues.

I listen to different types of music. Classical, traditional and modern jazz, blues and rock.

Really looking for your expert opinion. And if someone who has any experience with the mentioned preamps can share their thoughts, it would be great!

Thanks a lot!!!!