I think New Orleans should keep him.
His numbers are consistent everywhere else, except for his PPG this season. But that's because the squad isn't really defined on the offensive end. They need better direction. He had a wack postseason, but that's not exactly unusual. As far as Zion, his bag is limited, but he's as advertised, when healthy. He can do some damage. They have some decent bigs that can crash and body up nicely against other teams.
I think where they should make a move, is in getting rid of CJ. His pace doesn't even match what they're trying to do there. If they got a more dominant two-guard, they would be OKC level.