The reports of Hernandez bulking up seem to have some validity, and trading him may be less of an option than extending him - given his improved OBP and power - isn't he exactly the kind of veteran player we'd be looking to add?
Seranthony has good stuff, but Rios is the revelation, started at as a starter throwing 90-93, moved to the pen and jumped to 94-97, now he's at 97-99. There is definitely something with signing skinny LA pitchers and working with them, He was 6'3 185, probably a lot bigger now. Took a few years, but can't argue with the result.
I'm not surprised by Eflin, he needed the offseason to take advantage of his knee surgeries, supposedly added 20 lbs and I believe it, and they seem to have tweaked his mechanics to take advantage of his stronger lower body. Like Pivetta, it's not just that he throws 94-96, they both seem effortless and maintain that velocity out to 100+ pitches. That bodes well for maintaining and improving his FB command. He's improved his breaking ball and is working on a change which shows promise. Whereas Velasquez seemed to have reduced his velocity to gain better command, he was throwing more in the 93-94 range last start.