Look, I might be overvaluing these guys. If I were GM, the marketplace would tell me the value because I would be asking.
BUT, the Padres just got Margot, Guerra, Allen and Asuaje for a fairly expensive closer. Margot is listed as the 5th best OF prospect in baseball and #25 overall regardless of position by MLB. Guerra was listed as the 76th best prospect. Allen is a fine looking young lefty who showed out as an 18 yo. And Asuaje is projected to be a serviceable utility guy.
That was an ACTUAL deal. Meaning it was actually done.
Dahl was listed as the 47th best prospect. McMahon #50. Nunez is a catcher who isn't on the top lists. None of those players are players that the Rocks can't move or won't move. McMahon is blocked by Arenando. Dahl is blocked by Blackmon and Dickerson AND is an injury concern. Nunez is blocked by about 4 other catchers.
Miller, as a SP with three years of control left through the 18 season, is AT LEAST as valuable as Kimbrel who is a closer also signed through the 18 season (including option).
Would Colorado do the deal I proposed? Maybe not. But, it's the type deal "Coppy" should be trying to make since the cupboard for fringy pitching has been filled.