Barboza's chin isn't as bad as people say, it has more to do with his defense than his chin(which isn't that good either). Besides his defense, he has all the tools to be a top fighter/champ.
He is fast, punches hard, kicks like a mule and kicks very fast, has good TDD and improving jits, has good cardio(I don't know where the Silva and Overeem comparisons come from, but most of his finishes have been late in the fight and he always displays good cardio) and is a pretty big lightweight.
Benson Henderson vs Anthony Pettis 1 Highlight vid (300k views): /watch?v=MhTD2NhrdYY
Simon Marcus vs Joe Schilling III (Glory LMS) Highlight vid: /watch?v=5nAEJKikYzc