So Bard needs some changes... I think he's really weak.
His lane phase..
His Q moves incredibly slow, way too slow to reliably poke with, and the stun is so conditional you may as well only use it for disengaging. Compare this to supports with similar poking jobs, Lulu, faster missile, much more damage, more slow %, much longer range. Nami has a targeted ranged poke. Even Soraka's Q is more reliable because it can be used through minions. His Q needs quite a few things, more damage, more missile speed, or having a mechanic that dictates that his Q can't hit two minions, this would allow poke through minions, but wouldn't really call for an increase in damage or speed. This way he can at least get a stun off every once in a while.
W is a no brainer to get early on, but what purpose does it serve after laning phase? It's great to throw three of these down in your lane and not have to worry about too many health pots, but after lane... you kind of just run around throwing it on people as a pure speed boost. Maybe make the time it charges up scale with ult rank? R/0=10 seconds, R/1=7 seconds, R/2=5 seconds, R/3=1-3 seconds.. This would allow at least some use of his W come late game.
E is pretty good for me, it's useful for sneak attacks, and of course ganks.. I'm not sure I would even touch this skill, perhaps give an alternate cursor when highlighting a part of the skill you can travel through.
R is awkward. The range on the indicator does not match the actual radius of the skill. That should be fixed, and the travel distance can take some getting useful, but this skill is incredibly high skill ceiling. I found myself doing calculations in my stupid head as to what i should ult, the enemy or my allies (who had to wait for cooldowns, etc. And I had tried to cast it right on top of myself to dodge a Karthus ult the first time, and messed up by casting it way too late, but I had gotten the hang of it after that.
The chimes.. The chimes need to give scaling XP, even if it was just like.. 2 per minute, up to a cap. They are there solely to help Bard scale into late game. If you're Bard with like 60 chimes at 40 minutes, you're not going to be contributing much at all... But that's what this post is about, isn't it?
TLl;DR, what is Bard's role as a late game support? Other than the niche responsibility of ulting a single enemy FAR out of position so your team can secure a kill?