Firstly, he obviously has the talent to put up a sub-3.80 ERA with a respectable amount of strikeouts. Secondly, he's going to pitch the whole season, the Blue Jays will not be limiting his innings unless he really pushes the envelope and hits 210 in mid-September.
To date, his detractors have said that he's not 'ace'-caliber and while he could very well end up as a dependable workhorse over the next decade, he's never going to strike out guys at elite level or put up a sub-3.00.
Yet, after adding a lethal cutter (small sample size, but according to Fangraphs, the cutter has earned 2.7 wCT in his two starts, making it the second-best cutter in baseball so far), I think he's in for a serious re-evaluation.
I understand that his 3.65 xFIP shows that Kyle Drabek has gotten quite lucky, but since we're talking about Rookie of the Year, a 3.65 ERA would be well worth the accolade.
His main competitor, Rays top prospect Jeremy Hellickson is also off to hot start to the season as he struck out 10 batters in 5 2/3 innings pitched his first time out. Also on the horizon is Mariners rookie starter Michael Pineda, who allowed the minimum for a quality start in his season debut.
Obviously as I've said before, it's still very early, but keep an eye on these three hot-shot starters as they get into the stretch run as we could have a Rookie of the Year race not experienced in the American League in a few years.