Bard DPS is already on par with Monks and Dragoons on single target, with their 10% damage buff the only DPS class that will be behind Bard is the Summoner, and that's not even taking their pet DPS into account.

There shouldn't be a nerf to Bard damage at all. They need to make stuns and silences on the melee classes more reliable, maybe give Black Mage a silence. But don't touch the damn Bard.