Good list, I definitely would take Hagler as #1 from middleweight and Ali as #1 from heavy, maybe consider Floyd Patterson at cruiser?
I generally don't select fighters who never fought in the weight division officially but sure, you could add Patterson and Marciano as well for Cruiserweight.
In a mostly solid and enjoyable list Ring 80 Greatest Fighters of the Last 80 years ranked Pryor above Spinks. I found that stomach churning. He's got a pretty big win over Arguello, a respectable win over an old Cervantes and a few wins over quite middling contenders of the time. Just when he should have been soaring he fell into drugs and that was all she wrote. Spinks historic win over Holmes as a 6-1 underdog would cover all of that imo. Lopez, Marvin Johnson and the two Davis brothers more than cover Pryor's contenders that's for sure. Then we have Qawi and Mustafa Muhammad and some might even credit Cooney. There's just no damn comparison. He was also above the likes of Burley, Frazier, Jones Jr, Gomez, Foster, Napoles, Nelson, Hearns and Benitez. Hell even being above Tyson is a travesty.