Upgrading Cayin A88-T: what is next?

I recently purchased an A-88T from Cayin here on a lark. I am planning on keeping it (we have a second system to build) but am probably dropping it out of the main system. I have been using it paired with my McCormack ALD-1 w/SMC Platinum mod, and while it sounds nice and full, the detail isn't quite there compared with my normal amp (McCormack DNA-125 rev. Gold) and the low end definitely isn't as tight, as full, or as fast as the SS amp. Jazz and vocals are enjoyable on the Cayin, but complex orchestra and electronic/downtempo comes across a bit flat. The Cayin is a nice amp, don't get me wrong, but I am looking for a bit of that tube fullness without the trade-offs I am currently getting from the Cayin. Also, it perhaps runs out of steam a bit compared to the DNA-125. Speakers are Tyler Decade D1's, still breaking in at around 400 hours. They are musically pretty neutral, but full in sound, and put out a big, clear soundstage.

So, if I stay on the quest for a tube amp, what should be next? I am thinking a bit more power, more low end, a bit more detail, but still "meat on the bones".

FWIW, nothing against the Cayin. It actually exceeded my expectations, given the very modest price point. I didn't expect an integrated selling for $2000 new to be a world-beater. But, I assume one can get more for a bit more $. Any recommendations?
Have you tried tube rolling? I have this amp and put Genalex Gold Lion KT88 tubes in it. I like the combo.

Also, the amp will accept 6550 tubes, but you have to reset the bias. Some owners prefer the sound of 6550's to KT88's

I also replaced the 6SN7 and 6SL7 tubes with NOS Sylvanias. This did improve the sound, but not to the extent that replacing the power tubes did.
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Agree with Catama about trying some tube rolling. I also use the Genelex Gold Lion reissues and they made a marked difference to the sound - bottom end tightened up, more forward in the mids and overall a more balanced sound. Also tried NOS Sylvania 6SL7GT/VT229 and some NOS Amperex 6SN7's. The Amperex also made a big difference - more so than the 6SN7's.

Having said all of the above, if there is a power mis-match with your speakers, look at the more powerful Cayin (A100-T) or perhaps the Rogue amplifiers.
As far as the impedance goes, it is 8ohms nominal, dipping down as far as 6.5, and 90db/w.

Thanks for all of the suggestions. I was considering some tube rolling, but figured I wouldn't mind a bit more juice, no matter what. Looking at around 60 watts or more. The preamp tubes have already been rolled, but I wasn't using the pre section, only the amp. As it worked out, I found a great deal on an Atma-Sphere M60, so I am going to give that a shot in my system and see how it compares.
I think the M60s are close to the best amplifiers I have ever used; should be interesting to get your impressions - I love them and I have been through a lot of gear - they were the first amps that got me to sell my CAT JL2s without looking back, then again my speakers (Merlin VSMs)are very OTL friendly. Good luck. Oh, by the way, I don't think you will have any bass issues with the M60s:)