The knocks on him are somewhat out of his control. People knock his attitude and durability because he has a brother with those shortcomings, but I’d like to see a little more proof on the immutability of genetics before granting those points in total. He’s never been particularly young for his level- pretty average all over. Still, he dominated college ball, then ascended to the majors fairly quickly, so that’s hardly a drawback.
One positive which one might overlook, also associated with JD, is the performance itself. If they have similar natural ability, Stephen actually has the advantage that he has not experienced the combination of bad luck and fragility that has truly diminished JD’s ability. I have frequently heard the assertion that JD has lost power from his shoulder. Stephen has not had that problem yet, and without a guarantee that he will have it, I consider that something of an advantage. If he gets even close to his PECOTA projection of a .504 SLG this year, that’s pretty phenomenal for a rookie SS.
I don’t think he’s on the level of Reyes, and I think he’s decidedly below the SS Trinity when they were his age, but with Chase Utley and Ernie Banks among his comps, he has to be just below that level.