Really interesting ideas.
Typically, unless you have ungodly talent it will take 2-3 years for a young pitcher to settle in. Not everybody is going to be like Justin Verlaander. I've noticed some highly touted pitchers that a rushed up sometimes have a good rookie year, ala Kerry Wood and Verlaander. Then they trail off for a few years, and then gome back. Hideo Nomo is another good example. He had a stellar rookie year with his tornado delivery, but dramatically fell off after that. Felix Hernandez of the Mariners is going through the same thing. He came up in the 2nd half of the season, and then had a mediocre season last year.
Hitters are a different story on the other hand.