So I got the KT150 and Boom! Did the trick. I love em. Might add that the Mullard CV4003 for the 12AU7 is freakin wonderful. (I hesitate to say it because Upscale has already raised the price since I got mine a few months ago.) Subbing those tubes out is a $1500 proposition but well worth it IMHO.
BTW the ultralinear mode has a bit of an agressive edge to it, and I hear reviewers saying they prefer the triode mode. With the Mullards the ultralinear mode is smooth as can be, and I never prefer the triode mode now.
With that combo, it is better in every way you want to list. And the bass is amazing. Hard to believe that kind of bass from a tube amp.