While status resistance *can* add up to an appreciable effect, you really have to stack it. For example, Operetta alone probably won't see many silence resists on imps. Puppet's Operetta + Wind Carol + (from someone with high enhancing skill = not you) Baraera + Barsilencera + misc. Resist Silence gear ... *there*, you'll be resisting silence left and right.
But the tradeoff for that is that your bard buffs don't do anything *except* help with silence resist... and usually it's better just to, say, pop Echo Drops or have Silena casted, and use your regular buffs instead.
If your melees need accuracy, give them Madrigal (or Prelude for racc; RNGs usually won't need this and will be better off with 2x Minuet; CORs sometimes will need Prelude). If your melees need attack, give them Minuet. If you're high enough level that March isn't crappy, and their gear/food allows them to go without Madrigal or Minuet without much loss, swap out the unneeded buff for March and see how it works. Often merited sushi-eating melees at 75 will be best off with Minuet + March, but there aren't really absolute guidelines: give them whatever buffs they need most. Helps to talk it over with them.
Mages, of course, get their MP regeneration fix (Ballad 25+, stacked Ballads 55+), although BLMs (in a balanced setup, not a manaburn) may be better off with Ballad 2 + INT Etude rather than stacked Ballads.
Etudes, in general, are highly optional and often do more harm than good. Your THF may do a beefier SATA with those DEX and AGI Etudes, but they're missing out on Minuet for both SATA and the rest of their attacks for the next minute, and Madrigal for the rest of their attacks for the next minute, and overall they're probably worse off.
If anyone has a specific request, unless it's something painfully stupid like using Minne on a PLD (Minne is practically useless in the first place, and certainly for a PLD who should have stupidly large amounts of defense even without it), give it a shot for a few fights and see how it works out both for them and for you. If it turns out to be better, stick with it. If it doesn't, go back to what you were doing before. Don't assume that you know everything, but do pay enough attention that you're not following what's ultimately bad advice just to make some ignorant party member happy.
Probably the most tricky thing to do (and it's really not *that* hard) is to fuss with party positioning enough so that you can land Ballad(s) on certain frontliners, and the mages, but not other frontliners who won't benefit from the MP. BLU and PLD come to mind, and every now and then you may need to snag a DRK as well.
Finally, and this deserves boldface and all caps ...
DO NOT AOE BUFF WITH A STRING. (Targeted buffs are fine, so go ahead and use the string Etude instrument for those.) The range is variable and unpredictable (string buff range is a function of current string skill, relative to the string skill's cap at the level you learned the buff in question), and the upshot is that if you try to buff with a string, you generally hit people you shouldn't have. When levelling my WHM, I endured *far* too many parties with BRDs who used string for ballads and cheerfully regenerated MP for the melees as a result. If you want string skillups, there are other, smarter options: ask if you need advice.
