I have a few real draft regrets from my NL-only:
1) Rollins over Carlos Lee in the third round
2) Sheets in round 4 - Thought this was a major steal at the time. Webb was chosen 3 picks later
3) Kent in the 5th round (almost drafted Holliday instead) - I was completing the NL infield of dreams (Berkman, Kent, Rollins, Wright) and I thought Holliday might slip to me in the next round.
4) John Lieber in round 9
At the time, I don't think any of these picks were outrageously bad, but boy they don't look good right now.