I think if Riot honestly wants to make meaningful balance changes...
they shouldn't listen to the boards. But not for the reasons you think. Not because the boards are constantly begging for nerfs for a champion for a month or 2 straight (currently lux).
No, its actually because league consists of 67 million players. I'd say about 20% of those are smurfs so 53 million players. How many of those ACTUALLY go on the boards? Probably less than 30% of them. So that's at least 30 million players (I don't want to do math right now estimations op) that aren't contributing their opinion. 30 million that may have different opinions besides nerf lux and judging by another thread, nerf janna.
I think they should just send a poll out in-client or in-email asking 2 simple questions:
What champion do you think needs buffs?
What champion do you think needs nerfs?
This way the entire playerbase can actually contribute their opinion instead of the boards representing them when in reality, they're most likely gold or below (me), because lets face it. If the boards got their way. All the assassins would be deleted from the game, no one would be allowed to burst someone else down and the game would be less balanced than it currently is (which is damn well saying something).
And for those wondering what my status is in the game. I'm a silver 5 mage main. I mainly play brand, malz, and vel'koz. No I do not know lux nor do I play her often. However, I still know that being silver 5, I still don't really know shit as well as I should.
Also note that I said champion not item. Perhaps they could also send out 2 additional questions replacing champion with item.
As a final note, reminding that this is an opinion not a fact. Feel free to disagree, discuss, etc.
Also as a final final note, the point of this is to get feedback from the entire playerbase like riot wants. Not just 10-20% of them.