Red Mage:
This is another good choice. Like white mage, you get cures and an expanded library of debuffs. You also get fast cast at level 30, which will help you get your songs out faster. Off the top of my head I believe it's reduces the 8-second cast time of songs to 6 seconds, but I could be wrong. This helps a ton in getting those 6 initial songs out. I'd put brd/rdm 2nd behind brd/whm.

Black Mage:
Not a great choice. Black Mages get some decent debuffs, but your low mana pool won't really allow you to blast away with spells. Spell power will be slightly lacking as well. I wouldn't bother.

Summoner:
The main virtue of summoners is their huge mana pool. The problem here is that a summoner sub doesn't get anything to spend their MP on other than half-leveled avatars. Nothing else to say. This subjob sucks.

Ninja:
A good subjob if you're soloing. At level 20 you get dual wield and at level 24 you get Utsusemi. By dual wielding stat+ weapons like small sword or decurion's dagger, you get decent attack, further enhanced by songs. Do not think that you'll be a good soloer though. Bards just aren't built for soloing.

Thief:
The only use for this class is treasure hunter and steal. Past trying to earn some gil, there's not much to recommend this sub. Only use this combination if you are farming.

05 - Bard Abilities

Squenix kinda shafted the bards with their abilities. Here is the full and complete list:

Level Name Effect
1 Soul Voice Doubles the effect of songs (2-hour recharge)
5 Resist Silence Silence resistance up (passive)
25 Resist Silence Silence resistance up (passive)
45 Resist Silence Silence resistance up some more (passive)

And that's it. Soul Voice is only really useful when you positively absolutely need to land a sleep spell. For things like Paeon or Minuet, it simply doubles the effect. Thus, Paeon III will regen for 6 hp / 3 seconds, Ballad will regen for 2 mp, and so on. Once you cast Soul Voice, you will have to re-cast your songs for the added effect. Usually, I just use this whenever I want to. Unless you're in an area with a lot of aggro, it's not worth saving up.

As for the Resist Silences, there is some debate as to whether they even work. It's okay though. We get kick-ass songs.

 Working a Bard
A bard is there to make the party as efficient as possible. Thus, the #1 priority is to keep the right songs on the right members of the party at all times. In practice, this becomes quite a bit harder than it sounds.