Yes, he is a good ninja but he's over doing it thinking he's stronger than anyone. Then getting angry and getting himself killed when he's over whelmed because he couldn't find a way to counter using his all seeing sharingan.
Alright so his brother died to protect what he loved the most, his younger brother, and his village. And what does Sasuke do in return?
He wants to not only kill the people that set his brother up, but destroy one of the things his brother loved, Konoha. Like wtf? Your brother died to protect what he cared for and now instead of just getting revenge on the elders, you want to destroy what he gave his life and happiness for, because you think all of Konoha was up in the scheme to kill the Uchiha.
Summed up, he's cocky because he has his sharingan but when it can't read what's comming his way, he panics and nearly gets killed ...twice. He's gay because he ignores all them hoes that would jump on his nuts on the word. Naruto's gay too because he's always thinking of Sasuke so .. yeah they can be gay together.
And he's emo because he doesn't care about anything .. he shows no emotions, but when it comes down to his brother Itachi .. he falls apart crying his eyes out.