Rather than new menchanics or drastic changes, I think the Bard class would benefit from more options and abilities:
New feats:
Fast Performance:
Prerequisite: Bardic Performance ability, Perform 5 ranks, Dexterity 12 or more
Benefit: You can start a Bardic music effect as a move action
Normal: Starting a Bardic performance effect is a standard action
Counterpoint
Prerequisite: Bardic Performance ability, Perform 10 ranks, Fast Performance
Benefit: You can combine two Bardic performance effects in one Bardic Performance.
Swift Performance:
Prerequisite: Bardic Performance ability, Perform 15 ranks, Fast Performance
Benefit: : You can start a Bardic music effect as a swift action. Addtionally, any performances that require 1 minute of continuous plaing require 1 standard action instead.
Normal: Starting a Bardic performance effect is a standard action
Project:
Prerequisite: Bardic Peromance ability
Benefit: Increase the range of your Bardic Performances by half.
New Bardic Performances for the dead levels:
Captivate: A bard of 16th level or higher with 16 or more ranks in perform can captivate a target with an effect equivalent to the spell dominate person. At 20th level, this ability functions as dominate monster instead. The dc for this ability is 10 + ½bard’s level + charisma midifier.
stabilizing Performance: A bard pf 4th level or higher with 4ranks in perform can sustain her allies negating the need for stabilization checks during her performance. A sustaining song lasts for 5 minutes or until the virtuoso stops performing, whichever comes first
Restorative Performance: A bard of 7th level or higher with 7 ranks in perform can use this ability to remove fatigue and cure ability damage as per the spell lesser restoration.
Song of Fatigue: A bard of 10th level or higher with 10 ranks of perfrom can use this ability to render enemies fatigued.
Song of Exhaustion: A bard of 13th level or higher with 13th ranks of perfrom can use this ability to render enemies exhausted.
In addition, a brand new use for the perform skill. I though that high perform modifiers should function like spell focus but for bardic performance:
Bards who improve their performance ability not only gain access to new class abilites, but also improve the abilities they already have:
Perform DC, result
15 increase fascinate DC by 1
20 increase suggestion DC by 1
25 increasediscordant performance DC by 1
30 increase frightening tune or paralysing show DC by 1