Well, it's not like I hate the amp. I mean, at least it's UL, right?

IMHO, the greatest benefit of UL ops is the greatly lowered
output impedance... It's leagues lower than pentode mode, and
much closer to triode mode. The best thing is that you don't
give up much power compared to pentode, and it's about twice
the power of triode.

So what the low output Z means is that you can throw away
your NFB loop. Just disconnect it entirely. You will probably
have to adjust some gain earlier on in the amp to compensate
for the loss of NFB, but you can also use this "extra gain" for a
presense control or other active EQ types. The Baxandall type
of active EQ that Kevin O'Connor uses in The Ultimate Tone is
very effective and only uses NFB around a single stage. To my
ears at least it is not nearly so offensive as that which is
wrapped around multiple stages--and ESPECIALLY not
through the OPT and connected to the SPEAKERS.

Once you throw out that traditional NFB you will be welcomed
to a place where NO AMOUNT of overdrive or peak signal
will sound bad. Well, I take that back--There's still one more
place left to go, and that is to drive the output tubes with
cathode followers, sourced from a negative rail, and directly
coupled to the output grids.

Then you no longer have grid blocking, and you can make
MORE power since you can pull some grid current. There is
no end to the dynamics here... as you crank the shit out of the
output stage it will clip, and since it has no NFB around it it will
NOT sound like traditional output tube distortion. It will be
much much more euphonic and very sweet. You just
CANNOT make it sound bad at all!

It helps to have a nicely distorting output tube--in my case it is
the unbeatable and unfortunately NOS EI KT90.

But actually I have patents on all of this shit, so if you use it, I
will sue you.