Sounds good, I like your wife already.
In my less powerful Cayin A88T, I changed my 6550's to KT88's, and definitely prefer them. They sound very much like my vintage Fisher 80az that I sold to Steve at VAS.
I think preferred by type change rather than brand change, but ....
I got these somewhere (mine appear less blue that this photo).
https://www.amazon.com/JJ-KT88-Glass-Vacuum-Single/dp/B003FOAC3S

Next I blew a 6sl7 or 6sn7 by putting them in the wrong socket. 1st time for everything. I was shocked how much I disliked the replacement pair I chose, and Brent Jesse let me exchange, happily the 2nd choice sound exactly like the OEM branded ones (who made them for Cayin?).
When my friend brought his Dehaviland Preamp to listen here, we changed the rectifier tube, we were both shocked at the difference.
IOW, the small ones can change the sound as much as the large ones.
It's nice you can bias yourself, my Cayin has internal adjusters, you need to take the bottom off, keep it powered on, and get to the adjusters way up in there without touching something else. At 77, a bit shaky, I had Steve do it for me.