Yea, at least one bard is needed in every end-game raid. Whether for healers MP, or Foe's for extra magic damage. Bards deal sustained damage and are highly mobile, so even though you don't see the big numbers, you are always attacking through mechanics, where classes like monk and dragoon may have to separate from a target, bard keeps on with the pew pew which narrows the gap as far as DPS goes.

Ideally, though, you will want to level both pugilist and lancer, since their cross-class abilities will be required for end-game raids. Internal Release (pugilist), Blood for Blood and Invigorate (lancer) mainly. So play them and see how you like.