Since around 70 champs, we've had 6 bans.
Now we have over 130 champs, and still only those 6 bans. I'm not even going to remark on the balance issues and number of strong champions; there are simply too many champions to ban, and not enough bans to handle it.
Would 1 ban per player be too much to ask in Ranked/Draft?
The problem is that with more bans is that it doesn't fix any problems. When you look at the data, some champions are banned even though they aren't pivotal to winning or losing a game. They are merely perceived as being a pain in the butt and no one wants to deal with them.
Why do I ban Blitz? It's not because he's strong, it's because his pull is so annoying that when I support I don't want to play against it. If I didn't ban him, would their team automatically win? No, not at all, I could counter with morgana or just not get pulled. But I don't want to deal with it.
On the flip side, there are champions that are more powerful than others, and they are usually either picked or banned in any game. If we allowed the possibility for more of these champs to get banned, would that fix the problem? Probably not, since the next-most-OP champ would become the new standard, and nothing has really changed.
DotA has less heroes and more bans. And some heroes are disabled in Captain's Mode, which is their "tournament mode", because the devs have the humility to admit they're not perfect.
Maybe Riot needs a dose of humility.
yeah but riot keeps 70 of those 130 champs balanced into the dumpster so we're basically in the same place as before
Yeah and we got a few more perma bans with the new mages. 
Once League reaches a certain level of content, the only way to create a balanced competitive game will be to limit the available champions for competitive play. If anyone is familiar with Magic the Gathering's pro tour, I believe LoL will do the same eventually.
Normal matches will have all content available. (Standard Format to continue the MTG analogy) Ranked and competitive matches will be restricted to a certain pool of champions. (Type 2, in MTG analogy)
This is already done to a limited extent with patch changes. Various champions get buffed/nerfed and the meta has micro changes respectively. Also, I'm not advocating this change, it's just a hypothesis I have that addresses the growth vs. balance issue happening with LoL.
More bans wouldn't hurt. but I do love how Riot is always adding champions !
I think 1 ban per player would be fine, either now or within a year or two. Don't think we would ever want it higher than that, but just giving each player a ban, considering the size of the champion pool (130-10=120 champions left) seems totally resonable.
What confuses me is that Riot always goes on about wanting people to use bans to prevent the enemy from countering them. This never happens in low Elo because you usually can't put together a coherent team comp with clear counters before the ban phase, and rarely happens at the pro level because the pros know who they're fighting and ban to intentionally weaken the enemy team comp. Allowing each person to ban would allow them to do a better job of preventing themselves from getting countered.
The other issue is that so many people are convinced that first pick has some huge advantage and use that as an excuse to not give them a ban, which is only partly true. First pick gets to pick whoever the hell they want, but they also give the entire enemy team the opportunity to counter pick.
12 bans how about we ban all of the junglers? or all of the supports? how about we ban out an entire role of the game all the adcs?
