In my opinion, PLD is in a good state and is really low on the priority when it comes to gameplay changes, it cycles on a 60s and its filler must manage Divine Might and Atonment. That's already way more than WAR or DRK.

I do agree Divine Might felt like it was meant to be expanded upon, at least integrated to the job gauge.
I think PLD used to be like this back in Stormblood? You needed to have 80% of your MP to make a full combo, but there was the 60s cooldown.

Removing the cooldown and basing it on MP, I can predict Paladin would be absolutely bonker by doing its burst, exiting combat to regen MP, doing its burst again and cycle until the end.