As for +/-, I think it's a useful stat at the extreme ends. If a player consistently has a high +/-, I think it says something very good about the player. Conversely, if a player consistently has a low +/-, it says something very bad about them. For sake of argument, "consistently" probably means for 1/3 to 1/2 of an NBA season - not just 1 or 2 games.
I'm not sure if Baldwin ever even had the ball in his hands; and I think he is only effective with the ball in his hands. That's not an argument for more playing time for him; I just think it's a fact.
This article is a bit dated, but it has a good discussion of the overall value of +/- vs PER as predictive stats: https://m.huffpost.com/us/entry/5190651 For general information’s sake, Napier sports a 14.34 PER, while Pat’s is only 9.16.
