I hadn't really considered Charlie Blackmon as a possible Cubs trade target, as he's only been a regular center fielder for two seasons.
But then I looked again at his 2015 season, which was good offensively in quite a number of ways. He hit .287/.347/.450 (although WARNING COORS FIELD FACTOR: .331/.390/.500 at home, .238/.300/.395 away from Denver, though 10 HR on the road, seven at home) and stole 43 bases, third in the National League. He posted 3.2 bWAR in 2015, though showed up with a negative defensive bWAR (-0.6). I can't say I'm an expert on defensive value ratings, so I'll leave it up to those of you who know more about that to weigh in.