I’m actually thinking that you don’t have to be fleet footed to be a bard, though obviously that helps with perhaps dancing/performing while telling a story. but being a big guy who tells stories and charms the ladies would also make it easier to “persuade” anyone who’d want to fight you to think twice about it. some large guy comes in, tells a bunch of jokes and stories, persuades the bartender to get drinks all around for his merry friends, and suddenly you wouldn’t have enemies, only friends. and those friends could warn you if someone was talking shit behind your back. thus you could plan or at least be aware ahead of time if some sort of conflict would come your way. i like the idea of playing a character like this and doing the equivalent of “Ghost” in Deus Ex, where you kill no one except the main bosses/etc.
all that being said, you know i’ll have like 4 daggers hidden away under my cloak, in my boots, and up my sleeves 
i could see the bard and thief concepts blurring really well together in the game if the systems work out correctly.
anyway, that aside complete, here’s what i’d like to see for things a bard can do:
- sing
- collect stories, jokes, poems, etc
- play instrument (get item, learn item through minigame, perfect instrument)
- combine sing + play
- dance and/or perform
- combine dance + sing + play
- woo the ladies (possible dialogue based minigame). perhaps as you tell stories or perform in taverns the barmaids or women in the crowd gain interest in you and will spark a conversation that ends in… well… you know… babies!
- gain money from doing most of the above items, along with reputation, positive morale.
- be sought out by the local lords as your reputation increases and earn big bucks, perks, new clothing/items/etc for grand royal performances
- having “bard battles” where two bards, you and an npc, play instruments, dance, do all the above and have the audience decide who is best.
- build special campfires and have certain herbs/potions that make those listening more susceptible to your words. e.g. you get threatened by bandits around your fire, you casually add another log to the fire (same time adding some herbs) and the thieves end up helping you with supplies because you’ve drugged and duped them.
- write your own poems. these performances would not have voice over dialogue but you could “read” a self-written poem and based on word structure, meter (from punctuation, new lines, perhaps even a way to add that meta-data as you write it), length, and possible keyword content (forests, animals, love, war, profanity, etc) you can continue your prowess as a bard. it’d be even cooler if afterwards the npc’s pick up these poems, and by word of mouth or other mechanism you find a copy of your poem you wrote in the next town over several weeks later. super stretch goal with this one.
okay wow, i know some of those are definitely not going to happen but i think these would be really cool to do and help sell the bard “class” for sure! let me know what you guys think, feel free to criticize/add/modify the list as you will 