Any High End Tube Preamps with *gasp tone controls?

I'm all in for a Loki TC placed in a tape loop. I use one and the change it makes when needed far surpasses any potential down side. Used between the amp and preamp, I'm not so sure. If you don't have a tape loop, I'd seriously consider placing it between the source and the pre-amp. FWIW.

Well I don’t know what kind of an equalizer you’re looking for but, FWIW, Schiit has a 6 band equalizer that has both XLR and RCA and 2 channels as well. Pretty ’good’ and relatively inexpensive ($300 +/-). I use one.

ON equalizers incorporated into equipment as well as outboard have three things that affect the sounds that they alter. Frequency center, for example - the bass control may be centered anywhere from 30hz to 120hz (or more). This range also has slopes, i.e. fall off, and breadth. Variations in the bass control center and slopes controls the breadth. Gets kinda complex. Then there is other equipment which might center the bass control at 60hz, 100 hz, ad infinitum. But they all call it just plain old BASS. I've seen integrated amps which allow you to change the center point up to 200 hz. Wow, imagine that. Now there are tone controls in the mid-range and highs with accompanying options. 

The message is 1) Figure out what range of bass that you want to hear and 2) what your prospective units spec's are when it come to their tone controls. What you get is up to you. :-)

What 

If you can afford it, sure. That remote control will come in handy in finding the tone you are looking for when adjusting for sources like records and CD's. For some room or system correction, no so much. You won't be fiddling with it that much or often.  Sonically I've never heard it but I think it might be hard to distinguish the sonic difference between the 2 six band eq's.  If you put this in a tape loop it's easy to distinguish the changes made by the eq. If you have in-line and use the switch on the eq, not so much I think.