I think the main issue is simply that gear are not average, they are situational.

A good piece of "enhances debuffs", +accuracy, +MND, +STR, +haste, +MP or something would probably be a good start. Armors that collect all vital stats for a hybrid job, instead of forcing people to swap around hundreds of armors just because no armor works for two things.

I'm pretty sure a RDM, with enspells (1 or 2, I have no clue) and haste and accuracy would deal moderate damage. I recall my M.kris COR upping the "per hit" damage by 300% with enspell from RDM sub. Like it went from 8 to 8 + 16. (Numbers randomly picked, no facts). People just are too obsessed with "But the WAR hits for 400 a hit!" to think anything less than 300 per sword swing sucks. And we all know RDM will never do 300 per swing.