I wasn't actually replying to you, I was replying to Mook, who took your list and expanded it to include all players under 24. For anyone who didn't already understand the team impact on plus/minus stats, that expanded list makes it even more obvious that the quality of the team is much more of a factor that the quality of the individual player for this particular statistic.
Collins pretty much falls in about the middle of the Blazers in Net Points. He is 6th of 14 players at +44. Connaughton has the highest Net Points at +112 and Harkless is last at -86.
So, not bad for a rookie. Like Connaughton, Collins' Net Points are a function of which other guys he's paying with and the quality of the opposition (other teams' second units), but at least he's having an overall positive impact. Which is a good thing for a rookie.
BNM