He's had a terrific first seven starts, but it's still just seven starts. There's nothing wrong with letting a guy go around the league more than once and show he can still dominate hitters after they've had a chance to adjust to him. Is it true mastery of the level, or just a hot streak? It takes a little more time to know the answer.
I'm all for challenging hitters, but the Peter Principle is a terrible development philosophy for pitchers. Not saying you're advocating that.