Well never had his paths and would use them from the sidelines as they would drain chakra faster and would actually make Nagato easier to beat thanks to genjutsu.At first I thought that only Hashirama (unlikely) and Madara (likely) would win against Nagato, but then OP got more accurate and stated it's Nagato without paths... well...
Yeah, as I said, Nagato with paths, or even his paths ONLY would stomp everybody on this list apart from two guys I mentioned pretty easily.
If it's Nagato only, then that's a big handicap. But still, Naruto alone would not be able to defeat him (as we could see recently), nor could Itachi or Kabuto. Maybe Minato, but to my mind he would need help as well.
As for naruto, hes stronger since then and wont as stupid as he was back then as Kurama would be his intelligence.
BM Naruto<<<<Nagato
KM Naruto>Nagato