Well got pretty good bard and i just had 2 ideas how to make it better:
1) change animation of song cast. Almost everyone lags because of it. I know like only 2 man out of 20 who don't lag when i cast it.
2) Well its my opinion, but if in future there will be several songs available, i think it will be strange that bard will be able to buff different persons with different songs. It is like singing several songs at once. In real world that's impossible. I'd rather make aoe song when you activate it, for like 90sec.