No, you're not intimidating looking. You've got a great smile and look plenty good. Unless a guy is intimidated by a girl who is good looking, then I don't see why they'd be intimidated.
There may be other factors such as your height (are you strikingly tall or short?), or your demeanor which play into this. Think about your normal actions. Are any of them something that would make you seem unapproachable? Being standoffish, being too loud and boisterous, or coming off as arrogant can all cause this. For some people, even plain old confidence in a woman can intimidate them.
From my point of view, you are very attractive. Speaking as a shy guy though, I used to see girls like yourself and just assume I didn't have a chance! Perhaps you come across as the type that would take some convincing and would be a challenge, which isn't a bad thing!
Keep doing what you are doing and wait for the right guy. It doesn't hurt to show any interest either but just do it in a subtle manner.
Okay this is just my take on it, and I could be totally off but:
You are very pretty and have a nice style. You come across like a nice happy person. I think guys are attracted to you, but you look like a girl that a guy would have to "work" to get and if a guy is busy chasing honeys he is probably going to go for the path of least resistance. You are pretty and I'm sure guys would love to go out with you but you are probably going to have to show more interest and make it more obvious you're into them.