Yuri (my best friend, for those of you who don't know her) uses her own name instead of a pronoun. Which, to my knowledge, is a pretty childish way to talk, but apparently she would feel weird saying "atashi" or anything like that.
My experience in this is pretty much just limited to dramas, but you know, I've really watched a lot of dramas, haha. And honestly, from what I've heard, it seems like a guy can use "boku" in pretty much any situation and be safe unless it's really formal. I have very, very rarely ever heard a young guy use "watashi." Older men, it seems to be more common, but not for young guys, unless you're in a pretty formal situation. "Ore" seems to be pretty widely used though. Like, in pretty much any casual situation, young males seem to use "ore" unless they generally speak more politely than average guys, in which case they use "boku." Of course, like I said, this is just my experience from watching lots of dramas/variety shows/etc., so. But even on variety shows and stuff, guys seem to use "ore" a lot. You just wouldn't say it to like, your teacher or your boss or whatever. "Ore" doesn't strike me as being more manly than "boku," just more casual. Although I think girls using "boku" isn't unheard of, but that's pretty unusual, I think.
As for "atashi," it seems like almost all girls use it, from what I've heard. Seems to be really common. For girls, I guess it's either "atashi" or "watashi," really. Unless you're weird like Yuri and you just use your own name like a little kid.