NA won't ever be competitive again in the scene. Korea, China, or Taiwan will own the scene until the next big "e-sport" game comes around where we will get that year buffer. We just don't have the infrastructure like they do. Our challenger and diamond 1 solo queue is a joke compared to theirs. Hotshotgg recently tweeted about this same topic and got dumpster by the masses, but he was right. League in North America is all about twitch numbers and sponsorship. Why try to be the best when i can make 6 figures from riot salary and twitch in a relaxed setting. Unlike their overseas counterpart that play to make it a career in a cut throat environment. teams over there cut people and demote them on performance unlike here where you have to "retire" to quit if you are popular. Look at saintvicious hotshot, elementz etc etc popularity kept them on a team/coach not their play. At least Europe is semi competitive in regards to league. They have their season 1 trophy to fight and try and reclaim.
TL;DR Na won't ever be competitive in league in a worldwide setting.