6v6 PP Pentode mode

[wicked1]

A few years ago I asked about modding a pair of ampex 612 (620) 6v6 amps.
Ampex 6v6 PP Modifications
(Schematic is in that thread.. Power TX outputs 360v after the rectifier tube)

Basically, in the end I triode wired the input tube and the 6v6's, and removed the feedback.
They were never great, and back then I for some reason didn't wan to stray too far from the original schematic. Now I just want to reuse the iron.

Most of the fashionable 6v6 amps are all triode wired. I'm thinking I'd like to try pentode. So, finally the questions.

Why doesn't anyone do pentode 6v6 (hi-fi) amps? Is triode really that much better?

Then, any advice for pentode? I'll definitely add a negative supply and CCS to the LTP and regulate the screens on the outputs. I guess I'd just like any other advice on implementing pentode 6v6 amp.

(Final note, someone in that old thread suggesting trying 6l6's. I know the circuit I was using wasn't set up for that at all, but it did work, and the power TX's seemed to be able to handle the extra heater current w/out any trouble. Plus, I'll most likely be removing the input tube which frees up a little more heater current. So, I could probably use 6l6's or something.. but I don't know the exact specs on any of the transformers, so maybe it's best to stick to 6v6.. just throwing the possibility out there...)

Thanks for your help! I realize these general opinion type threads aren't the most useful in the long run of the forum.. But I appreciate the advice and it does help.