There's a mod out that makes your non controlled party members more aggressive in combat and it's awesome.

I don't know what the linking policy is on this sub, so I'll just leave the name of it. It's called "Most Combative Team Members" on Nexus Mods. They actually attack more often and fill up their ATB gauges. But they also know when to play defensively too, which is impressive.

If you think enemies are dying too quickly because of the mod, there's another mod called "All Enemies HP Increased" that increases all enemy HP times 5. Yeah, it's kinda crazy, but they kinda balance each other out and give regular mob fights a nice length.