You haven't acknowledged it yet when you say things like "Trout benefits from his speed but that should have no bearing on his ability to hit a baseball. "
The era he played in means everything. Even if he was clean the pitching was not as dominant as it is now. Anyone with 2 eyes and a radar gun can tell you that. There are probably as many guys cheating now as there ever were before, just doing it in different ways now.
As far as Trout hitting like Miggy, who knows. Know one thought Miggy woudl hit like Miggy is now the 10 years ago or so when he was Trout's age. Trout has all of the ability in the world. Good power, great swing skills, great speed, etc. There is really no weakness to Trout's game. Only way he can really improve on his game is cutting down on his Ks.
And wRC+ is the perfect stat to use because it's the only stat that weighs eras, park factors, and everything else in a way that actually represents value.
Harper pre-injury had a .973 OPS and was falling.
What's the excuse for his performance lately? Usually when guys come back from injury they don't stink for 2 months.