If I'm concerned about Woods Richardson at the very end of a rotation, I'm probably feeling pretty good about my rotation.
Now he IS walking a bit of a tightrope as evidenced by his roughly 4-ish xERA and xFIP. But I'm also okay with a 4-ish ERA from his spot in the rotation, particularly in his rookie year. If the velocity holds and his command of his arsenal continues, I'm not particularly concerned. I don't think he'll be much more than a good #4 pitcher but hey, every team needs those, too.