From top of the head: Jose Medel, Efren Torres, Susumu Hanagata, Horacio Accavallo, Santos Laciar, Vicente Saldivar, Gilberto Roman, any of panamians from 1970-80. Betulio Gonzalez, Hugo corro, Jesse Burnett...
Jose Luis Ramirez Miguel Angel Gonzalez Jose Luis Castillo This fighter's imo we're very good better than most people give them credit for, sadly they were in a very competitive era with lots of great fighters, Especially Ramirez and Gonzalez.
Jeff Chandler never gets talked about and when he does it's usually negatively. Guy could damn fight.
Other fighters worth mentioning: Alberto Davila Sumbu Kalambay Gilberto Roman Lionel Rose Marlon Starling Miguel Lora Betulio Gonzalez Yoko Gushiken
I'll cut and paste a post i made some time back about Freddie Pendleton. Probably talking a lower level than the OP is chasing but the man is interesting - At one point Pendleton was the best "bad" fighter in boxing i.e. the best fighter in boxing with a bad record. Let me summarize some key points - Turned pro at 18 and lost 4 of his first 6 fights before winning a few. He came off a basketball court with 1 days notice to beat Tyron Trice in the first round. Lost 4 of his next 5. Lost by a bee's prong to Jimmy Paul, ko'd Roger Mayweather, drew with top contender Frankie Randall then lost to 2 clubfighters before drawing Bramble and then ko'ing Fuentes in 15 seconds. When he was 12-12-1 Ed Gersh watched him sparring 140 champ Billy Costello and saw potential. He saw amazing moves but a bad record. He sent him down to long term friend and veteran trainer Larry Kent. After this he went 9-3-2. At the time Emanuel Steward said he might be the best 135 in the world among other things. In the early 80's he often accepted fights on one or two days notice. His previous trainer had taught him how to get thru fights unhurt. This led to close fights often going against him. Kent taught him the psychology of winning. He had him fight aggressively while still utilizing his speed and defense. He also taught him how to punch with full leverage therefor greatly improving his power. Freddie learnt to go out there and try to get rid of a guy if the opportunity presented itself. He may have been the second best 135 in the world at one point.