This might've already been suggested, but I couldn't find mention of it.

Now I'm aware that this is probably not the best idea for various reasons (like balancing and whatnot), but:

What if the Bard's songs' strength were affected by the character's stats?

Like having an increased MP/TP regen per tick, or a stronger Foe's debuff amount based on a specific stat.
This could be an added motivation for BRD to gear up.

It probably can't be linked to a tertiary stat, or the BRD would end up being too spread out, so maybe just tie it to Determination or something.
Just throwing this idea out there for discussion.

Please don't be too harsh

Also, greetings from a noob on the forums