THR = The High Road, which I'm told sprang from the loins for The Firing Line, like a gazelle.
If it's range gun you're looking for, I'd suggest a 4-6" barrel. Better velocity, generally more controllable and accurate, longer sight radius, and won't wear out your wrist after 25 rounds. In a .357, it still makes a big boom
K frames are considered medium frame revolvers, yes. If you have exceptionally large hands, you might find the factory grips a little undersized. However, K frames have a ton of aftermarket grips available, in many sizes, so it's easy to find one that might be better for you.
jmm