Ok you have two things going against you: 1. You are young. While that SHOULDN'T Affect you it will. People hate high pitched voices. 2. You are playing minecraft. There are literally thousands, possibly even tens of thousands of people doing minecraft videos. Finding a niche is good, but using one that everyone is doing (COD, minecraft, league of Legends etc). My Niche is good. It's TF2. There is a large community, but not a massive number of youtubers doing it (Star_, Jerma and a couple others are about it). That has helped me out a lot as well.