Lets talk Balance, chime in with your mains
A hot topic right now is balance, with quite a bit of negative criticism. That's not productive and as a community there's nothing Riot can take from solely negative criticism. As a community lets chime in on this thread on our mains, where we think they're strong where we think they have a weakness and try to go through and assess them as a champion to let Riot know our thinking as far as champs go.
Champs I main:

Overall as a champ Bard I think is in a pretty good spot. He has a lot of versatility with itemization being able to be successful as AP or tank in the support role. His clear strengths to me are: Burst damage from a support, lane sustain, self mana sustain, team utility.
Weakness: One damaging spell, short range on ult.
His kit:
Q: Only damaging spell, pretty good ratios. Theres really nothing I would change about this spell I think its in a good spot.
W: This is Bards heal, It falls off pretty hard late game. It does provide a speed buff. Riot recently buffed this by having a flat mana cost at all levels. It could use some love, but its not by any means unhealthy. I wouldn't change anything about this.
E: Magical Journey: This feels pretty weak in Bard's kit. I would add a CD reset on kill or assist.
R: This is a great spell, it takes some time to get used to the timing. I think it'd be more fun to play bard if I could cast my ult further, just to give my team more utility.
Overall Bard's health in my opinion 9/10

Definitely a snowball champ. People hate to play against him just because he zones you off just with his presence and angles. He also has an unreasonable buff by differences in hook clarity on certain skins.
Strengths: High Burst, good combo, strong passive.
Weakness: Snowball champ, no escape.
His Kit:
Q: This is basically his entire kit. It has a pretty reasonable CD. For what it is its pretty ok where it currently is. ADC's such as Sivir, Ezreal, Tristana all do well against this hook because they can escape it once hooked. Other ADC's have dashes that they can utilize to dodge hooks. Draven is one champ in particular that is very weak against blitz. However Supports in general have little counter play potential outside of morgana. Few supports have actual dashes. But supports such as Leona and Alister don't really mind being hooked. But anyway, He has a clear niche on an ideal laning phase, and yeah in ideal conditions he'll do great.
W: Months ago Riot changed this spell from a flat speed buff to a sudden Huge speed buff that gradually diminishes to a self slow. This was before Deadman's came out, and since the change they have leveled it out. However, in its current state you aren't actually making progress if you're trying to run away. The displacement/time for the same distance traveled is the same if you use the spell or just walk. Initially you can put distance between yourself and the enemy if you are retreating, but they will catch back up to where they were initially.
R: single target knock up, combo with Q. pretty ok for what it is.
R: AOE burst silence, with random lightning proc. damage wise i think its fine, silence is fine. The passive proc is annoying because you can't clear wards in dragon pit at a low level by yourself.
Overall Blitzcrank's health in my opinion 6/10
But I invite you as the community to chime in with your champs you main.
Overall, as a player I am bad at dont know how to balance. I think his mushrooms should last longer and he should have a global quote when people die. This would further help him in putting people on tilt. I also feel like omega teemo is the best skin in the game and needs to be better somehow.
Idk... I mained him top but he's just not good enough there anymore. I think he fits well into the jungle though.
Contrary to popular belief he's in a rough spot right now. And buffing him too much would make him dominate. All in all I just think he needs to have his E reduce attack speed again.
In a good place atm
Needs his previous nerf reverted. He just needs a little more width on his q.
In a decent spot. Any buffs would make him op
I think with the addition of
Shaco's in a good spot right now. His damage is higher than ever (which, imo, is fine as an assassin) but he still has a lot of options for counter play. Unfortunately a lot of people like to bitch about him (even before the item) instead of actually taking the time to learn to play against him.
Very flexible champion, can play at any position viably. Very strong against melee champions and short range champions. Doesn't fare well vs high range/mobile champions that can either stay out of range of Q and W or dodge them/break the chain.
An assassin that excels early to mid game. Contrary to popular belief, she isn't that difficult to counter. Disrupt the W and most of her damage goes away. Dangerous if ahead, awful if shut down. I wouldn't particularly mind nerfs, with the kit she has, she'll be strong no matter what.
Very safe. Personally I prefer the triforce+essence reaver build as it's stronger early and continues to bring a lot more damage until blue gets muramana, but I break out blue on the occasion the enemy team has a lot of melees or assassins. I think blue build could use a nerf but the triforce+essence is up to par with the other marksmen.
The 'Ezreal' of AP Mids. I think as of right now she's a pretty safe pick. Decent at all points of the game, perhaps a bit too strong. If I were to make changes to her I'd give her W a scaling mana cost to punish her for maxing it first, then fix the wonky targeting of her W and R.
In a fine spot. Heavy damage is gimped by low range and delays. Doing surprisingly well vs the influx of assassins. Wouldn't change a thing.
Underpowered. The ult damage increase was a step in the right direction, but he'll need more than that to be a worthwhile pick again. I think the bounces should be smaller, but add in an extra one so the range stays the same. As of right now, his Q is incredibly easy to dodge no matter how good you are at Ziggs, and I think reducing the amount of space between the bounces would fix that. On top of that I'd lower the ult cooldown from 120 to 120/110/100. What good is an ultimate if it's on such a huge cooldown? I'd rather have a lower cooldown than the damage buff they gave him.
Very strong and versatile pick. Can top, mid, jungle, and even play as an aggressive support. Strong early, but falls off quite a bit late. All damage is mitigated simply by walking to the left or right of his flag when he does the EQ combo.
A tad underpowered. I get that she's supposed to have a bad early game, but right now her damage is so low that the bad early game is transitioning into a bad mid game as well, and that's when she's supposed to be at her strongest.
Strong spot right now. I wouldn't say she's overpowered, but the new masteries reeeeeeeally suit her. Whether a mid or a support, she packs a punch at all points of the game.