When thinking of an initial contact or acquaintance with someone, I have learned through experience that it's generally BAD for either me, or the other party, to come off as overly friendly and familiar. (I'm an adult male Aspie BTW.)
I swear that just about every time I can recall (in my adult life) that someone was overly friendly and familiar as I first got to know them, turned out to be a bully. It's like they were trying to prepare me for what followed, blindside me, so I wouldn't see it coming, and it bypassed my distorted intuition. It didn't make any sense when these covert bullies gradually turned 90 degrees, then 180, from their initial selves - almost like a Jekyll-and-Hyde metamorphosis unfolding - and really caused me a great deal of grief and suffering. It got to that point where I called them on their game, and got the line "how dare you, after all I did for you" - typical retort. In more recent years, I was able to use my intuition to see through this mask, so I guess that's a good thing - too bad I had to learn thru trial and error though!
Conversely, I have tried the overly friendly and familiar approach on others in my youth - stepping outside my comfort zone - and was told by an NT friend that this is generally a bad idea b/c people tend to think of you as weird. So I self-calibrated to a low-key but not spaced-out initial approach. In retrospect, I can see why I was given this advice - people would see something like this as odd - sometimes I wonder if it's b/c they suspected I might be a bully or psycho, but then I realized no, they probably sense some sort of desperation due to my inherent difference, and this turns them off.
Either way, bad for both parties - I guess there's that unwritten rule that "there's something up with him/her" if that person is overly friendly and familiar.