Also, there really isn't anything about sai that would make him selfish.

He's basically cast away all emotions so he can devote 100% of his interests towards the sake of Konoha.

What's selfish are people like Naruto.
Konoha doesn't want Sasuke back, he's a traitor.
Sasuke doesn't want to go back to Konoha.
So for who's sake is Naruto trying to bring Sasuke back for? Nobody but his own and Sakura's