As for why Sasuke wanted to leave, the reason was quite simple.
After witnessing the strength of Orochimaru and Akali, Sasuke grew dissatisfied with his current rate of growth. It was not that he failed to realize he was growing steadily; under Akali's influence, Sasuke was much more rational than his original counterpart. Having filmed videos himself to earn money, he knew all too well that making money was as difficult as eating shit.
Yet, rationality and emotion are often two different things. Knowing the facts clearly in one's mind did not mean one would not feel discontented, for Sasuke's fundamental nature had never changed.
Chapter 96