Naruto becomes Hokage, which Jiraiya never did want to be, and still doesn't want to be.
Sakura becomes an even better, and far more skilled medical nin than Tsunande is now. She's already showing the potential that she could be way stronger than Tsunande is now.
Sasuke overpowers Orochimaru...oh wait...that's already happened :x
So, if you go by all of that, NaruSaku actually stands even MORE of a chance of happening, since Tsunande/Jiraiya failed, but since the series is all about SURPASSING...NaruSaku actually has a very high probability of happening
I agree with you.