My mare is basically both!
When I need/want her to be spunky, she has no issues being horrifically silly, but when calm push button-ness is needed she's right there too. I guess you could say that she's a fiery pushy button...If you ask right she will do anything for you but if you ask wrong, well, you're just gonna have a super boring ride. haha And maybe why I like her being rather push button-y is that it took me 3 years of riding bucks, rears, and other general crazy to get her here... I'm to the reward stage and I'm ready for it. haha
Personally, she's my favorite kind of horse. I like being able to trust my horse to behave correctly (and I don't mind spending the time to train a horse to understand what I want) and I like feeling safe while on horseback but I don't mind having a "conversation" with my mount. She can question why I'm asking her to do something but I don't want her to blantantly refuse to do something just because. I don't mind her doing silly stuff either, as long as she's being silly in a way that's not going to kill us both.
In my mind, a horse with an attitude problem is one that behaves in a "to heck with what you want, I'm going over here/doing this and there's nothing you can do to stop me" way. I hate hate hate horses like that. It makes me sad since horses aren't born that way, they're made that way through rough treatment and they're almost impossible to get back from that point because they've learned to not care what their rider wants.
In my book, most horses do not have attitude problems. I know a lot of misunderstood horses that are labeled as having attitude problems, but with the correct handling those issues would be gone, just no body cares to look at what's going on from a point of view other than "this horse is bad" or "this horse is soooo dumb" etc.