First of all, for liabilities sake, I will never use a tube with an anode cap. I realize there are many tubes that would be great to design with, but beyond my personal use, I am not willing to do it.
As for a two EL34 per side, P-P 30W-50W integrated, the technology used in the EL84 amp would apply and it could be FANTASTIC! Like I said though, when I mention EL34's, a lot of people yawn.
The EL84 is unique because it is not expensive (new stock), and it really produces a beautiful sound. Yes, it would take eight EL84's to produce the power I want, but I believe this has been a successful formula for Manley (Stingray) already.
I am targeting a $3K-$5K price range for this and it will likely be a factory direct business model. This will mean that we can offer a LOT more amp for the money!
In that price range, for 30W+ in a tube integrated, if you were/are in the market, what are you looking for?