If this unlikely scenario were to occur then I predict that a fury of FB's would trash Sasuke to no end. In fact, if the haters hated Sasuke enough already then this probably would've turned off the casual Sasuke fans I believe. Jiraiya was a loved character that the idea of getting killed by Sasuke who some people believe to be an annoying, whiny emo brat (not my opinion), would be the ultimate slap in the face. Pain was indifferent in that this was his introduction arc and was used to hype him plus he respected his former Sensei to some degree.
As far as storyline goes, well there would've been no going back for Naruto. Naruto would've have still searched for Sasuke but not to necessarily bring him back
