I agree, lots of good looking young arms on the Pirates. You never know how injuries will affect them, but if they stay relatively healthy their pitching is scary both starters and pen.
Their hitting still look pretty mediocre/below average. Ozuna is past his prime as a hitter and is an absolute liability in the field, Reynolds I think has seen his best days, Lowe and O'Hearn are upgrades on what they had but neither really strike fear in me. The 19 year old will likely be a star, but probably not this year.