Naruto compared to Sasuke, eh?
Yes, both Naruto and Sasuke can come off as selfish, but the difference is the intention behind it.
Naruto wants strength for the purpose of becoming Hokage.
He wants to be Hokage to have everyone acknowledge his strength.
Sasuke wants strength so he can get revenge.
He wants revenge so...he'll have revenge.
Look at where these choices lead. Granted, neither one of them could know entirely what lies in store for them down their respective paths (they ARE just 12, after all). But they should have an idea, at least. Hokage is, simply put, an honorable title. You become Hokage, you do great things (at least we know Naruto would, even if by his own special "charismatic" means). But what's gonna happen to Sasuke?
"Sasuke, you've finally killed your brother and avenged the death of your entire clan. What are you going to do now?"
"...uh...oh shit."