I already mentioned him but you are right about Kalambay. Such a highly underappreciated boxer with a lovely style to watch who showed that a skilled fighter like Mike McCallum had his limitations.
I like Thomas Hearns, I like Ray Leonard but Kalambay made it look so fluid. He did not have the resume those guys did or the career, but he had something I liked which was natural. What a great style and movement. No wasted energy.
I have to include the old self taught master...the graduate of the school of hard knocks himself, Joey Giardello...and when he felt like getting on shape, Willie Pastrano...and...his close...razor close rival, Harold Johnson.
I disagree Morales has better fighters on his record and more of them, not by loads but clear to me as i like Barrera as well but I put Morales just ahead of him as many other people do. Morales has the best win by far in Pacquiao. Barrera's best win besides Morales was probably Hamed, Morales KO's him for me. Barrera also lost twice to Jones whom Morales destroyed in 4.
It could be argued Howard Davis Jr. might have been...from a detrimentally "pure" perspective. I say to his detriment because he was practically anti-punching power. The "purest" boxer doesn't remain undefeated for too long, he has to have at least some stopping power to really be effective. Unless I'm abstracting my definition of "boxer" too much.