I would do each of them at least 6 times for the progression achievement(for dicho-upgrade), and by then you should know which one is the most efficient use of your time. That said, the demiplane of decay HA seems to be the fastest one for me.
If you are after Remnants of Tranquility then Fate Rewards the Bold, We Make Our Own Rewards, In Defense of Health and Lxavnom Labors (I found the 1st 2 the quickest to do). These are the missions Jumbur mentioned above. I would occasionally grind out AAs in Into the Temple (B).
I was thinking of the TBM progression achievement "lesser spirit armor": https://eq.magelo.com/achievement/23778100/Lesser-Spirit-Armor-(Group) The reward are rankups in "hero's vitatlity" and "hero's fortitude", and is a required step to upgrade the class dicho-spell(I think). You basically need to do 6 pohealth HA's + 6 codecay HA's + 6 demiplane of life HA's + 6 demiplane of decay HA's.
https://naroggsplace.wordpress.com/lesser-spirit-armor/ this site has walk threw info that might help Good Luck