Didn't read the whole thread, but here's my 2¢ (probably redundant):
I'd use all tube if I could: nothing beats it for tone IMO.
Why don't I? Weight is a factor, but here's a bigger one: what I LOVE about all-tube amps is how they sound when pushed -- i.e. power tube clipping. Nothing sounded better than my vintage SVT rig run LOUD.
The problem is that that perfect "push" factor occurs within a narrow volume range. Below that, the amp is too clean. Above, it's too dirty. So: even if weight was not a factor, I would not want to have a tiny tube amp for quiet gigs/jams, an average tube amp for moderate gigs, a big tube amp for big gigs. And what do I do in a new venue when I don't know how loud the band will play? Bring all my tube amps? Set them all up onstage, so I can change to the appropriate one? I know, the practical answer is to bring the biggest and use an OD pedal if it's run too quietly. But I'd much rather use pedals with a clean, lightweight amp. That way I can get my desired overdrive level at any volume.
Dirt pedals are very good these days: I can get really close to the TubeTone I loved -- but only occasionally got to dial up -- decades ago. I can get it at any volume, and without all that weight.
P.S. I'm seriously thinking about getting a 100W all-tube amp being developed by my buddy Jonathan at Reiner Amplification. It should come in under 40 pounds, but probably won't be able to handle my loudest gigs.