I was getting some weird loss of volume a short while back, so I swapped tubes. It helped, but I think the cleaning I did actually did it. The old tube probably had just worked loose over the years. I hadn't touched the thing ever, and it's the original.
I'll see if I can find a pic, but I drive my pre really hard normally. No cutting, only boosting EQ points, and normally set the VU so that I'm playing into the red or on the edge. I would almost always play with a bit of grit and then use light drives or boosts to hit the front harder and get tons of grit from the tube.
I can't recall the tube I threw in there, it's an old one that is not common and sits between an ax7, and which ever of the at7 or au7 that's "middle of the road" gain and I'd say I prefer the original more as a whole. Mostly because the output volume lined up closer to the tube bypass volume. It definitely is cleaner sounding though. I don't know much about tube rolling as a whole though, but I believe there's some threads out there talking of people doing so on ABM's.
Yeah, idk if it's just an ashdown thing (though I doubt), but I've found that I tend to prefer to only boost and not set anything below flat. That and I prefer an upside-down smile or close to it normally on graphics. Doesn't always sound the greatest solo, but seems to shine for me in a mix.