Shuster's FA was 90.6 mph with 8.0" of rise. That's poor velocity with below average movement. Needless to say, that isn't going to cut it as an MLB SP without elite control or superb breaking stuff, not even a #5.
The SL was 82.9 mph with 2.0" of horizontal break and 0.6" of "rise". That's below average velocity, close to average horizontal movement, and above average vertical movement. This is a decently average-ish pitch.
The CH had a 10 mph delta from the FA, with 4.7" of fade and 5.2" of "rise". The velo delta is plus, but the movement well below average side to side, and average vertically. If this is his premiere pitch, I don't see how.
All in all this looks to be a very mediocre arsenal. He's basically a LH version of Ian Anderson minus 2 grades on the FA. Without absolute pinpoint command of the FA, I don't see how Shuster is anything more than a fill in SP who will be looking to catch onto non-contenders within the next 5 years.