I can't speak to the level of competition that he's playing against, I have no idea. I'm surprised there haven't been more articles touching on that. It is pretty important to know who Harper is putting up these numbers on.
It would be interesting to see breakdown of Harper's numbers versus the opponents #1 starter and versus the other starters. At the majority of community colleges, there is often only one decent pitcher amongst the staff (if even that), usually guys that got drafted and wanted to go to college for a year to increase their stock. But the rest of the staffs are usually future beer league material. I don't know how helpful those types of splits would be, but it would be interesting nonetheless.