Letson is probably the most exciting of the night for me. He or Knoth, but as a 11th(?) rd pick out of a cold weather state and limited exposure, to be pitching at low A already and show the type of stuff he did and the different pitches, that's incredibly impressive.
Knoth is great as well, but you more expect it.
As for Pratt...he's just one of those kids that looks like they've got the irrational confidence that they believe they belong from the jump...and I love it. You have to have some of that to thrive at such a young age, but he just seems like a kid who lives and breathes the game and loves playing and grinding. When you combine that with that frame, bat speed, his hands, that's a helluva package.