Ok so this is a Noel bashing topic. Here are my thoughts.

Noel really was the main villain. When Lightning had the chance to stab the heart of Chaos she refused and just beat the crap out of Caius. You are suppose to defeat him. Noel refused to kill him. Instead he should have killed Caius and took the heart of Chaos like he was born to do. From there he would have unlimited Yuels to reproduce and let mankind live on.

Instead he waits to kill Caius in Valhalla! That let Chaos flood the timeline and pretty much let the devil out of hell. He killed the world doing what he did. If at all he was going to kill Caius don't do it in Valhalla. Go back in time and kill him fair and square and take the heart. Problem solved.

His character refuses to follow any prophecy. That is where he hurts the most. Even in lightning returns he fails at this. Sure it all works out some way in the end but he has an authority problem.

How he treats Snow is another problem. He does not even try to be polite. That don't bother me that much but I see your problem there. He should be more considerate.

I will also note I think Noel is a really good character and besides what I said he is still my favorite FF character. The fact that he is destined to be the last is what drove me to like him in XIII-2.