There is a link of BiS?

baleful gauntlet on +5 its better on acc or spr?

For multis where speed matters, lucia TMR or anything that gives a speed bonus

brutals are more tactical and one size fits all is impossible, but generally you want damage up TMR for mages, xiza for anything that needs AP

Equipment doesn't matter so much as long as its +5 for 13 or 15 damage bonus, healing mace doesn't matter because clerics and arithmeticians already have healing skills, latter case there is no charge time

The only real choices right now are sort of self terminating based on context, chell tmr and soul of thamasa only matter in pvp because most enemies don't have spr or res, with the exception of brutals and towers...

Anything other option is just reactive to context, do you need an alex ring or baleful gauntlet for an accuracy bonus?

This really isn't the kind of game where BiS is much of a convo. The weapons are all obvious, while the armor/accessory/VC and even Esper is up to you and what kinds of enemies you're facing.