I have the SE84UFO25 paired with some 7 year old Omega single driver speakers. The synergy between these 2 components is amazing.
I think when using a low power SET amp like the "25th anniversary" one is better off with a good pair of single driver speakers. I think a lot of members of this forum would tell you the same thing.
Years ago before I got into the low watt SET and single driver speakers concept.
I had a PP high power tube amp from a very reputable amp company and good 2 way speakers.
I never really liked the system as I had to play at (for me) very high levels of volume to get the detail and nuance of the tune.
I think in my case I prefer the single driver crossover less speaker because the signal does not get trapped in the crossover at low level volume and all the detail that an amp like the 25th can produce is not lost.
In my humble opinion I think you should consider the crossover less single driver speaker concept with an amp like the SE84UFO25
Decware has great speakers of this sort and Steve will be happy to talk to you about it and he won't BS you.
Also Check out the Omega speaker web site
https://omegaloudspeakers.com/Louis (the owner and designer) will talk to you as well.
Just a phone call away
Thanks
Bob