Sean O'Grady and Greg Haugen both exemplified what it means to be serious business in the ring. Both men had workrates that were off the charts and both always fought with heart. Haugen's matches with Pazienza are nothing short of pure classics in my honest opinion. While I certainly like O'Grady, I would seriously have to favor Haugen. Greg was simply far more proven against rated opposition and was tested in the heat of battle more than a few times. Sean's win over Hilmer Kenty for the WBA lightweight crown was a major acheivement as was attaining 70 career knockouts and fighting 26 times at the age of 15. It can't be overlooked however that O'Grady was protected by his father managed him, and fought an overabundance of underacheivers. Ultimately, he was beaten on the vast majority of occasions that he stepped up. His career record of 81-5-70 looks good at first glance. But, when we look a tad closer, he is actually more like 2-5 against quality opponents. I think Haugen's counter punching techniques and overall toughness makes things very difficult for Sean to get anything done. Haugen on points or late stoppage.
I think everything you're saying has merit but for some reason I'm still going to take O'Grady. O'grady is listed at 5'10" and I think height and reach would play a factor in forcing Haugen to lead a little more than he'd like. I'll take O'Grady by decision. Of course Leonard would eff both these guys up ;-)