I gig with a Bassman 100T with the Bassman 410 Neo cab for medium to large stages (up to festival-size. I use a 50 watt tube rig for small to medium rooms) and I never feel underpowered, mainly because I’ve got foh and monitor support as needed. Mic the cab, don’t use a DI, or do both, but micing the cab will get you all the power tube glory. After years of reading about your exact situation, the majority seem to have volume issues in rehearsal more than onstage. Of course how dynamic everyone else plays is a big factor. Also, the 100T is not the silver face 100 you’re talking about, different animal. But just saying a quad of 6Ll6s pushing out 100 watts can do the job. How well it does the job depends on the design, and I’ve never used one live so I can’t comment there.