Sure Black Beard give of a little villain vibe. But honestly, have he done anything that truly define him as a villain, except maybe killing of his nakama? If that can even be counted. He is a pirate after all. And as he said himself, he had been looking for that devil fruit for a long time. It was the only one he wanted. And a rule that his current crew had prevented him from getting that fruit that he had dreamed of.

All he can really be accused of is being ambitious. He finally found the fruit and did what he had to do to get it. He wanted to skyrocket his name and fame, and for that he needed to take a pirate with a 100+ million bounty. Anyone would do and Luffy was the first but got away and Ace was the one that confronted BB, and the defeat of him gave BB what he wanted.

To me he is very Luffy-like with the exception that he can make his hands dirty when he's forced to. But other then that he laughs all the time, is a little goofy, he seems to be a believer of grand dreams (refering to when he beat Belamys henchmen and defended Luffys way of thinking). I want more proof that he is really a villain before i start labeling him as such. To me, people like Crocodile and Moria is more villian material. Hell even Kid or whatever his name was, is more of a villain. And Luffy fought right beside him.