I’m sort of with author Alexander (“May This House Be Safe From Tigers”) King on this one.
One of his stories featured a weird guy from Greenwich Village in NYC who wound up arrested for bizarre behavior on multiple occasions, but who he considered harmless - contrasting him with the straitlaced but highly repressed sorts who were liable to do real damage when they went off the deep end, like throwing heavy office equipment out their window on the 30th floor.
Certainly all the people who have punched me in the face (quite a few) have been bog-standard check-shirted Caucasian townies; nothing diverse or ‘weird’ about them. Except the willingness to punch people in the face I suppose.
Ha!..Maybe its you 
For me, my anecdotal evidence knowing some multithousand ‘non-weird’ people and around 100 weird people the % that have assaulted me are in the neighborhood of:
0.0003% normal people assaults on me
1% weird people assaults on me
I don’t know what’s meant by “dangerous”… do you mean a person more likely to commit a violent act upon you, more likely to talk you into doing something stupid or lead you astray, more likely to drag you down socially by being around them?
Personally I’d consider a weirdo less likely to dangerous, though of course it depend how weird you’re talking about… the person who comes close but doesn’t quite fit in is very different from a person who goes out of their way to make it known that they don’t want to fit in.
You see the weirdo coming and are on guard, or probably have nothing to do with them… and I’d say most weirdos are quite aware they don’t fit in and will try not to let it get any worse by actually doing dumb shit.
The handful of truly dangerous people I’ve met have all fit in quite well wherever they were. It was their ability and propensity to know how to blend in socially that kept their dangerous or unpredictable personality traits hidden from others until they lashed out. They also didn’t seem to have any desire to change… they could lead happy social lives and just blend in to a new social scene once the last bit of trouble they caused blows over.
As an analogy I’d say you’re probably less likely to be harmed by a weirdo walking down the street wearing a medieval costume a sword on his hip than by a normal looking guy on the lookout for victims carrying a concealed gun.