Now here is the kicker: I am getting older and want simplicity and reliability in my system. I don't want to be screwing around with tubes and chasing down issues. Also I can't lift 75lb amps any more. So I am in a quandary, I like a certain sound but may not achieve it the way I am going.I'm not sure why 75pounds is a thing, but FWIW, our MP-1 preamp weights about half that, and that's for two pieces, not one. So if you can mange 15-20 pounds you'll be alright. FWIW one of the founders of BAT was a customer of ours before he went into business.
One tip: whatever preamp you get, check with the manufacturer to see if it supports something called 'AES48' which is the balanced line standard. If they say 'no', or don't know, or don't know what you're talking about, then the benefits of balanced line won't be realized with their products! The benefit of balanced line is immunity to ground loops, immunity to the 'sound' of the interconnect cable, the ability to run long interconnect cables without degradation and rejection of noise that might get impinged on the cable as it goes from point A to B.
What this means is that if your preamp supports the standard, you won't have to use expensive cables to get them to sound right and an expensive cable won't seem worth the extra money. They'll all sound extremely similar. I own monoblock amps so I can keep my speaker cables short and long interconnects. The cables are Mogami which are not expensive by high end audio standards and I run 30 feet of it. At audio shows I've run as much as 50 feet.