Hey Yuu, I have to agree that your app is a bit short, but from what you have written I can tell there is potential for you to write a long and detailed application.
Like others have said, looking at the guide and past apps will help you a lot. I think you were on the right track with your reasons/weaknesses, now I think you just need to elaborate on those points. The little details are what cements the reality of what you are saying about yourself. A big thing to also do is to state alongside each of your weaknesses how you plan to handle your weakness. It can be as simple as pledging to control it to the best of your ability, but it's still a crucial thing to mention.
Overall, I am a +1 for you as a staff, but for the app itself I am a +/-. People who don't know you ingame would need more info then this in order to see you as a good staff member.
