Bronies are now a pretty relevant subculture in the world we live in today. I would definitely like to get more responses if you don't mind. I pretty much agree with some of the things you've said about 'em. I really see this thing as a big phenomenon over the Internet and not so much of a big deal outside of the Internet. I've met only one person who knows of a brony he knows personally. That's the closest I have met a brony.
As for the last person who responded to this, yeah... those adult stories (they're fanfiction, by the way) are pretty messed up and I think I read one and I did not like it. But hey if that's your bag, that's fine by me. In fact I knew someone (not gonna mention names here) who wrote them and actually shipped (shipping is when you pair two characters in a fanfiction, they have like a romantic relationship in the fanfiction story) characters. Another thing that I don't like is the "clopping"... clopping means to masturbate to ponies (fanart mostly and I've unfortunately seen some of this fanart). It's rather disturbing.
Yeah, I was a brony for a brief period of time. I just had to get out of it. I guess I outgrew it. However there's going to be a lot of others who will be bronies the rest of their sad lives. I'm not saying that bronies are sad people who are losers, but a great amount of them are weak though... I will say that.