It sounds very reasonable to me but I'm a HDH so I don't know if my opinion does you much good. I think it's a great list, and I've also had difficulty with specifics in the past. I'd tell her it doesn't seem like she enjoys sex very much, and she would of course just say "yes I do." So I'm sure telling her specific things you'd like her to do would be a step in the right direction.
It sounds like she's already somewhat willing to step outside her comfort zone which is a good sign. I'd probably emphasize to her that you're not looking for all of them or even any specific one(s), certainly not right away. I would think that if she wants things to improve, she could find one she's comfortable with and as she gets more comfortable, she'll be more willing to try the others.
