Hartshorn's swing rate is 37.3%. If he was an MLBer last year that would be second lowest in the league behind Juan Soto.
I think if I was looking for nits to pick that's one I'd keep an eye on. Pitching is dire enough in Low A that you can probably do quite a bit of damage by just refusing to pull the bat off your shoulder. I'm thinking about James Wood, who had stellar K/BB numbers as a 19 year old in A ball leading into (ironically) the Juan Soto trade.
James Wood had pedestrian contact numbers even then while Hartshorn's are quite good, so it's not apples to apples. Also I don't want to yadda yadda that Wood has turned out quite good. But just steeling myself for why/when Hartshorn's K/BB numbers likely go from insane to just good when he finally runs into pitchers with a little command.