Definitely a promising trade. I like both players a lot as multi-year rotational players in San Antonio.
Barnes cancelling out bringing back DeRozan is the immediate highlight. For those who've forgotten, Barnes was the ultimate blue-chip recruit in 2010 and played two very solid years at UNC. He contributed heavily to the Warriors 2015 and 2016 le teams. He's supremely Spurs character material, well-spoken, highly intelligent. Oh, and a starting SF who shoots 3's! Imagine that.
Bjelica (pronounced Bee-Elite-sa) is a deadly 3pt specialist. Last year he pulled this off against the neighbors to the east. Do it RC tbh.