I already own my Smoke Signal so I don’t really have a horse in this race, but I would argue to keep it as it is.Yeah I like the blue channel as is, but it's nowhere near my favorite clean preamp. Obviously putting UA in for the clean channel would affect the dirty channel as well as the dirty channel uses both tubes, so I'll take a look at the design and see if it would make sense.
I've also considered making a separate individual preamp with just the dirty channel, but I really like having both options in one box so that idea isn't as tempting.
I LOVE the blue channel, clean or with the gain cranked. If someone prefers the UA for clean tones, maybe they could BUY THE UA. Why not offer a little diversity in your stable