I've got the Audia little brothers, Flight Two Int Amp & CD Two, in my Living Room setup (not yet posted) paired with Focus Audio FS-888s and twin Velodyne subs.
With 3 other systems that are all tube or have tubes in the mix and not ready to commit to another set of tube amps in the living room yet, I chose Audia as a stop gap. When auditioning, I was impressed with the balanced sound, control, specs, & build quality. To me, this was a SS amp that a tube lover might appreciate, especially so when compared to other decent quality similarly priced SS amps auditioned. After living with them now for almost two years, by and large, I am quite pleased and do not feel at all that the FS-888s (90 dB @ 4 ohms) are wanting for power.
That said, like you, for some time now, I experienced precisely what you did with respect to feeling that there "was something missing". As I listen to the other tubed rigs far more frequently, the differences were / are readily apparent. A few months ago, for a change of pace, I decided to drop my Primaluna Prologue 2 in the mix just for a change of pace. The driver & input tubes have been upgraded to high grade tubes & it sounds really quite nice; ironically, approaching SS like sound. After a few weeks, a funny thing happened - I actually started missing the Audia amp and realised how much I appreciated its virtues . . . clarity, tonal balance, sense of power, and very good bass delineation. I have since decided to hold off on any changes for now and simply appreciate the current system for what it is.
Accordingly, my vote would be to give it a bit more time. If, after more time, you still feel the need for a change, youd still have not really lost anything and will have solidified the reasons for wanting the changes in the first place. Good luck either way.
Cheers,
Garry