As the OP has pointed out Bard has obvious weaknesses. However, I don't like how one sided this thread is so I'd like to offer a different opinion:
First of all Bard is a champion that requires mastery and you have to play SMART with him. For example his ult can change the course of a game.
- Dive towers at little to no risk. Especially early.
- Protects your team against heavy AOE comps.
- Allows you to chase down fleeing opponents.
- Freeze the enemy team while they're taking drag or baron. This allows your jungler to get a no contest steal.
Secondly Bards Magical Journey is really under-appreciated,** it is the ultimate bait and switch**. This ability sucks for lane but if coordinated can provide a beastly way for junglers like Udyr to close the gap. Also... :
- You can cast it at fountain to provide a long tunnel to take you and your allies nearly to the exit of the base.
- Bait enemies to follow you into your team waiting on the other side.
- Makes contesting Baron easier as your whole team can walk down from the back.
- Travel across the entire enemy base wall to rapidly destroy base towers.
- Allows for awesome team splits around enemy towers. Placing your passage beside enemy turret allows your bruiser and someone else to go in behind enemy lines to eviscerate everyone in an epic death sandwich.
I'm not going to disagree with the OP that Bards heals are weak when used on demand. However they're a lot like Batman, they need prep-time, but when you've got a low health ally who picks up 3 fully charged heals it can make a huge impact in a scrap. In regards to having them get stepped on by enemies, if you're letting the enemy step on them and they're not paying for it, you're playing Bard really wrong. The only time an enemy should be allowed to even touch your heals is if you're using them as bait.
Let's not forget that bards heal can give a huge early advantage to your jungler by providing 3 early heals for them. Doing this allows for an easy clear and then inturn a safe pre-shop gank.
Bard's Q can make spectaular plays and it feels awesome to get a stun off. I do agree that it is probably the weakest part of his kit though. It moves slowly, does a depressing amount of damage, and it's range is kind of awkward. Cosmic binding could probably use a quality of life buff, however, it's not too far off from being in a good place.
His passive is interesting... you really reed to be smart about when you're roaming for chimes or else you'll kill yourself and your laner. Personally I think the chimes spawn a tad too slow to let his passive scale effectively into the late game but for the mana and deep warding opportunities it provides, it makes it worth it.
So to summarize, people just got to give him a chance. He's REALLY powerful when in the right hands.