Think about it. All the nerfing of Soraka, Sona, and such have lead us to... A heavy cc burst 100-0% lane game. What was better?

My point is, we don't make the meta. Riot guides it with their constant nerfing of the game, instead of letting it evolve. This bot cc burst game would probably be just as effective before the passive support nerfs. Nerfing is fine and all, but they typically go a bit far as seen with this. Cait was played mid quite often, and destroyed people, she got her early game nerfed. And, look at her now. She doesn't really fit in bot lane, and the buffs Riot are giving her are hardly signifigant, don't fix her problems, and I feel the nerfs she got before (that being hurting her early) are greater than how they are buffing her now. New champion releases also made her worse off, and made the early game nerfs just a slap in the face. They took away something that worked because many people QQed about not being able to beat her playing a mage.

These are just a couple examples championwise. Another one is itemwise. Since season 1 we have lost 50 stacking "armor pen". 30 from Sword of the Divine (That also had the highest attack speed boost in the game), and 20 from stark's (amazing, overpowered, godlike) aura. This limited armor pen choices in general, as there is now a lower "cap" you can hit. Both of these items I would use with melee casters, as brutalizer gave armor pen too, so these would (sotd to a lesser extent) give you lots of "good stuff". So, it's not just the 10% mastery that lead to armor pen being found less. So, now we see last whisper every game mid-late. In fact now most changes (like mf's ult or twitch's remake) supposibly have "better scaling" just because last whisper exists. This in itself isn't real balance, just because an item exists you are forced to get it if you want to scale better. Overall this has limited choices available to people build and itemwise.

Point is, you can try, but if you make a meta that "riot doesn't like because it's OP", are using items too "effectively" (spellvamp nerfs, re-itemization), or thinks is "boring" (passive support play) they will step in and change it. Learn to play their game, because it is their game. They won't sit back and let it evolve on it's own. I honestly feel the reason why we don't have as much diversity is because of their interference every two weeks.