Dude, I was obsessed with FF7 as a highschooler, because I was an emo-reject kid who felt alone in the world. Cloud was basically ME. Now I go back and play FF7 and I realize that it's mostly shlock, although there are some pretty good moments.
You don't need to relate to Mario because Mario doesn't have cutscenes and story elements. And when it does, people press the fucking skip button faster than lightning. See Mario Galaxy... did anyone really care about the story?
In Paper Mario and all those Mario RPGs, the Mario Brothers are mostly silent and the drama is more in the villains and side characters, and the little story vignettes that come out of those encounters. Mario is just a tool for the player to make things right.
Gordan Freeman is similar to Mario, he's the everyman that has no voice and is thrust into situations. He never talks. The story is in the characters that surround him, Alyx and the rest all have decent characters, and it's a typical man versus other style plot. So Freeman is just a tool for the player.
Dante has lines, a persona, he talks in cutscenes, in the past he's had personal goals that aren't just thrust upon him by other characters. He acts for himself, and the player inhabits that body as him. If the player thinks that Dante's goals are silly or unrelatable, he might stop playing.
Oh, and if you're posting on NeoGaf, you are definitely not the target audience for this character... that's a very different kind of teenage dirtbag.