I originally liked the idea of having multiple good amps for variety, but I have learned I get more from going all out on just one great one these days.
It's more like. . .Holy crap! This sounds so freaking great, I can't imagine it getting any better. Everything is perfect now, so why bother looking elsewhere.
House of Cayin, House of GEC, and House of Elrog are all my houses that I love and will dwell in forever.
The amp is only half the story, and the tubes tell the rest.
I originally liked the idea of having multiple good amps for variety, but I have learned I get more from going all out on just one great one these days.
My situation is quite different from yours. For one thing, I can't fit any of the big tube amps that you and others rave about here. I mean, really, truly can't fit them in the cramped space of this home office.
But there's another difference that's just as important. I crammed 2 complete systems into this space:
The main system includes the NOS DAC, DDC, headphone amps, amp/preamps, speakers, sub, class D amp & electronic crossover. It's on the far right side of the long, L-shaped desk, with a big desktop computer the digital bitstream comes from;
The side system includes a different DAC (NOS/AIO), SPDIF converter, headphone amps, and laptop that's my main machine
Both DACs have dual RCA outputs live at all times, allowing 2 headphone amps to operate simultaneously in each system
In the main system, thanks to the very transparent RCA pass-through output on the Icon Audio HP8 amp, I can actually connect 3 headphone amps (or amp/preamps) simultaneously (one of which is always the system preamp)
And each system has a different mix of cables (USB, interconnects, digital coax) that I upgrade periodically
NOTE: None of my amps are the equal of a mega-tube amp, but some of them are very powerful and sound terrific (ie, Wells Audio Milo & Cavalli Liquid Carbon v2/side system; V281 & Icon Audio HP8 in main system). Plus each DAC has its own strengths.
It's a lot of moving parts. But in practical terms, it's relatively simple. Sometimes I listen to headphones on the side system; other times on the main system. I can & often do move the headphone du jour (selected from 5 or 6 good ones) from one amp to the other during a single listening session. And I listen to the speakers/sub ~12 hrs/day, way more than I listen to any/all headphones.
So at least in my case, variety is the whole point. For me, the grass is always greener on the other end of the desk...