What do you perceive the shortcomings of your current system to be?
You are committed to a vintage speaker array but want to upgrade all else, and I'm curious to know where you want improvements.
As you know, I have old Quads, Decca ribbons , and a pair of Crosby Quads as well as some vintage Quad tube amps and other 'old' stuff, so i 'get' your system, though I am not currently using any of that equipment in my main system right now. So, in my mind, the first question is what is it that you think your system lacks, and what is it that you hope to improve by 'upgrading' it?