Got a new set (replacing shit like Lone Wolf and Vigorous with Point Breakthrough and with Guard+2) and an actually appropriate Switch Axe (last one was Dragon, Z.Doragyurosu is weak to Fire instead of Dragon), and I'm playing at Adrenaline+2 (1.5x true raw instead of Vigorous' 1.15x). Had a few close calls and some VERY lucky moments regarding the Maiden charms (shouldn't rely on them, though) but most of this was essentially perfect play.
If I really went for it, I could probably reduce the time down to sub-5 but honestly that's probably because of the few moments where I lost some time due to getting hit. Not gonna bother, I'm happy enough with this, and I'm likely not going to try TA'ing Z.Dora anymore. I've had my fill.
Want to play the game too?
https://pastebin.com/QqAwZSTC
Here's a pastebin containing information on how to play it.
Or watch this video by SephVII...
Quite friendly for newcomers trying to set this all up.