Replacement for current speakers suggestions

Bogiedr1- you have good equipment. If you want more warmth, have you thought about adding a subwoofer or 2?

As for your comment about MC, nobody takes his posts and advice seriously. In this post, MC recommended x number of springs, then after somebody suggested more, then MC increased the # needed. Maybe 10 springs would be better? Maybe 12? Why this is misinformation, any isolation product for a speaker has to be designed for the weight of each speaker. If you put a spring that's rated for a 20 lb speaker under a 200 lb speaker, the spring will be fully compressed and will not be beneficial. Same goes for any number of isolation products, make sure you purchase 1 that can handle the weight of the component

I don't believe springs are any good at decoupling. My choice is IsoAcoustics, although I also like the SVS SoundPath Subwoofer Isolation System.

I think MC made the suggestion in good faith. When he is writing about audio, I listen to him closely. I second Magnepan 1.7's for what you describe. That tube amp you have will likely have enough oomph to drive them to pleasurable levels. I am 64 also, and wish you the best.

I feel for you my friend. I'm a bit younger but went through quad bypass a few years ago. I'm very lucky for sure. I think the Wharfdale's may be up your alley. I haven't heard them but the Lintons are getting great reviews with the attributes you seem to be seeking. They are large monitors that sit on short stands for like $1,500 or so. Crutchfield has these with free shipping plus something like 30 or 60 return policy so you can try at home. Dyns may also be something to consider. Wishing you all the best and whatever you select I hope it brings you happiness. Stay positive.

Maybe try the Sf. Warm and rich especially so with your M'tosh amp.  And in my opinion they are the best looking speakers if that means anything.  God bless.