First of all, why does everyone overestimate Sona's Q when it's weaker than Bard's? It always has been.
Second and beyond, his heals are (always were) really good when people cooperate with him. Ever since the Sona rework, he's taken up the place of 2nd best heals in the game, behind Soraka. He drops in this position as the game goes on. When he can't afford to put down shrines and let them bake in the oven, his heals fall off a lot, meaning he pretty much always needs to cast in on people or position them as matters of "just in case", wherein they often don't get used until after a team fight is done and everyone is recalling anyway. There's matters of sieging, but those don't seem to last very long nowadays unless you're playing ARAM.
The buffs consist of a lower meep recharge rate and higher ratios on his heal. Literally no stat changes, and if utility and nothing else was his only niche, than Janna outclasses him by a long shot. He has higher stats than Sona across the board anyway. (with the exceptions of attack speed, [useless] auto range [still has safer pokes] and mana regen. [still has less mana problems]
Back to the buffs, Ratios don't do all that much early game. Supports have just about no AP early game because they need to build up their sightstone and then their gold item with a lower income. Mid game is where Bard's heals fall off. At that point it's hardly worth even using the mana to cast it directly on somebody, and if Bard manages to get a fully charged shrine to help at that point, then he frankly deserves the value increase.
Seriously, I've read a guide to playing around Bard that said that his heals late-game are practically only speed boosts. They deserved the buff.
The meep recharge rate is also not any different than what he was already capable of. It's just now his poke patterns aren't gated by his meep cooldowns.
Generally speaking, you should avoid letting him line up his stuns with minions or walls. Counter-intuitively, to avoid his skillshots, you should avoid staying behind minions. (Unless they clump up and you can stay behind two minions, or if the minions in your lane are somehow arranged that you can farm while staying above 450 range behind minions) Bard's Q by itself isn't very impressive, and if he can't follow up with his meep autos safely, his poke is pretty meh. (Think Sona without any auto attack follow up) For that reason most Bards probably won't bother with their Q if they know they can't stun you unless they're trying to all-in you. He can only really safely poke from auto attack range without the stun if you position poorly enough to let him, if your support has 0 presence or poor positioning themselves. Avoid the stun and you shut down his offensive aspect pretty well. If his adc is making plays, that's another story, but that story is one of getting outplayed.
Maybe I've buried the lead here. TL;DR: Bard's meep recharge time is pretty worthless if you're playing correctly yourself (and is a minor buff if fights somehow last more than 8 seconds but less than 10, more than 16 but less than 20, etc.) and almost only lets him go in with his Q when it's off cd more often. The W changes are deserved.
