Briscoe, Satterfield, Tiger Jack Fox, Lloyd Marshall, Henry Hank, Henry Armstrong, Joe Frazier, LaMotta, Graziano.
McClellan and Jackson weren't brawlers. They set up knockouts. McClellan was a jabber and mover even.
No way was Gerald M a slugger. Boxer-puncher if there ever was one outside of Hearns. Julian was a precise sharpshooter.
He threw a lot of jabs and circled opponents, had amazing timing. Maybe you've only seen highlight reels of him.
I'm not sure if you're mixing McClellan with someone else but G-Man was actually a really good boxer-puncher who used a hard jab, great feet movement and placement to maximize his power, great body puncher (especially the left hand to the liver), and incredible timing with his right hand. His heavily offensive mindset along with his passion to KO opponents early gives that impression that he was a crude puncher but G-Man really did take his time by using his boxing skills before going for the kill. Problem is he always hurt his opponents very early on because of his great power.
Julian Jackson shouldn't be mentioned also. He was a textbook boxer/puncher who used basic boxing technique, good fundamentals, always looking for the KO but wasn't wreckless in doing it.