She was, however, did you take into account the multiple other times existing texts were quoted? As far as 'happy' scenes, remember, we are at a point where the kinds of things that used to be pretty close to exclusively found in 'happy' scenes are beginning to leak into the main event line. Also, remember that she is a shrine maiden outside of school and we aren't given the details as to why. She could just be religious, possibly a family connection to the shrine she can be found at on the weekends. Assuming she is from a religious background, we also don't know if she is only helping the shrine to be nice, for payment, or if she is doing it as part of her religion and we don't know what religion she holds her beliefs to. It could be Shintoism, which would make sense with the shrine maiden thing, or she could be a Christian. The stereotype associated with particularly devout Christians, especially in fictional media, is a person who is almost always talking about things with a religious connection, sometimes quoting scripture, sometimes just talking about what their deity would want or what their beliefs tell them about a specific situation.
There's still A LOT of unknowns about her, just saying. I could see the possibility behind your points, though.