The thing to do is get custom Iron with ~4k primary, and tap it at 10%, 20% and 40%. Tehn there is the pate z of the driver to modify the ampunt of NFB on top of tap %-age. lowe pate z means less NFB. Pentodes and the faux pentode cascode connnection delive the highest fraction due to the high plate z( horizontal plate lines, no? ).

L-C-L-C is probably the best idea for the PS. Good input choke in first pos'n, and a low DCR, low Hy for the second. Moror run oilers for PS caps. Rectifiers? too many choices. Hg-vapour? DH like 5R4's? IDH like 5AR4, or single diode like the damper diodes of 6AU4 ilk?

It always comes back to the custom OPTx, you need the taps where you need them, so might as well get a few and be able to mod the amp and/or experiment.
regards,
Douglas