Unless he's somehow hiding a hell of a lot of muscle in those videos, he's definitely overweight, and probably borderline obese. I'm actually fine with pitchers being slightly on the overweight side in general, provided it doesn't affect their throwing motion. I suspect, without evidence, that it forces them to use their legs more and probably reduces injury risk a little. He may be pushing it. Hopefully he'll get on a better diet / exercise program in the minors and convert at least a little of that into muscle and he should be fine.
I still don't like the pick though.