My preference is a Slugger/boxer. A guy that is dangerous and comes to fight but also has a solid defense and a good jab. Joe Louis, Arguello, Duran,Trinidad.
Duran was a brawler who could box, Sugar Ray Robinson was a boxer who could brawl. A few other examples
Screw being well rounded. I dont care what style a guy has as long as he's good at it and dedicated to his craft. I can enjoy a defensive specialist like Floyd putting on a clinic but i can also enjoy wilder losing 8 rounds in a row and then sending a guy crashing with a random hayemaker. I also enjoy back and forth brawls and guys like shawn porter who have a 1 track mind and apply pressure all night. "Invincible" technically sound guys who are good at everything and hardly struggle are boring. My favorite to watch for pure enjoyment is a brawler but as a fighter and aspiring trainer/boxing writer i enjoy the slicksters.
My preference is for a fighter. To me, that's a guy who is balanced and can box and punch in equal measure whether he is a highly skilled great fighter or a solid journeyman.
Duran's style evolved as he was champion. He was always attacking but the old wise men had him boxing pretty neatly at his peak. I'm thinking about the way he boxed DeJesus in their rubber match. Palomino as well.
I like at least the threat of a KO, so watching a defensive master run rings round an opponent with no thought to finishing them is a bit like watching a soccer team outpass another team without trying to score.