I've suggested something like that before.
This gives them an immediate reset on their salary. It also sends a local favorite in Payton Pritchard back to them. Pritchard's probably not a star in the making, but if you force-fed him for a year, his value would go up, and his rise would satiate fans during the rebuild. I think he could be something like a discount Brogdon eventually. Obviously all the picks are a big part of this as well.
Nesmith's probably the wild card. You have to wonder if he has some fans in front offices around the league. I still think his future is bright in the NBA. He reminds me a little bit of a 3 point shooting version of one of Billups old teammates - Rip Hamilton. But still, he has not produced enough to a good piece for any team that wasn't a fan of his at the draft.
How much better does this trade make the Celtics? Real question. I think Schroeder's edge is a big boost to the Cs. If you replace that with a relatively soft player that can't get to the free throw line with the new rule changes, is this team a lot better?
Another big question is ... why wouldn't the Blazers just trade Simmons? Simmons is probably a better assets than the sum total of everything in that trade package from the Cs.