I've been looking into this a bit myself. I've had some thoughts.
The soil mix from abg would likely work, my only concern with it is how finely ground the orchid bark is in ABG mix. I actually mixed some soil earlier, and used a coffee grinder to grind my orchid bark down more. Very powdery now, no scraping/impaction risk. Abg official is probably similar.
Microfauna I feel like standard springtails and isopods would be fine. They should be small enough the pacman ignores them.
LLLReptile has a list of non-toxic plants for use in vivaria, should be useful since you don't want a pacman accidentally eating pothos.
https://www.lllreptile.com/articles/...our-terrarium/
Good luck!