Few feat ideas:
Heroic:
Song of the Heart: Pre-req: Bardic music class feature. +1 to inspire competence or courage bonuses.
Music of Renewal Pre-req: Healing Hymn. Your healing hymn can be used to give all allies in the burst regeneration 2 for every 1d6 of healing up to a max of targets equal to your charisma modifier. Example, a 6th lvl bard with 18 charisma can target 4 allies and give them regeneration of 4. This uses up a healing hymn for the encounter.
Curse song: Pre-req: Bardic music class feature. Bard song effects can be used negatively on enemies. You must have the appropriate bard music class of the same name to use these effects.
Cursed Countersong: Targets in burst up to your intelligence modifier gain 5 vulnerability to thunder and a -2 saving throw penalty for charm based saving throws. This changes countersong to a standard action.
Cursed Inspire courage: Targets in burst up to your intelligence modifier get -hit/
dmg of appropriate level.
Cursed Inspire competence: As above, but skill checks.