I would not want her to sleep anywhere else

In the winter she sleeps in between us under the covers. In the summer she sleeps on top of the covers where ever she is comfortable. I think it is a personal preference.
I have read "the reason you should not let them sleep with you is because you are the Alpha dog and you need to establish dominance. If you do let them sleep with you they need to be invited up and only allowed to sleep at the foot of the bed. They should not be allowed to push you out of the way."
Take that for what it is worth. My Yorkie is my baby and I treat her as such!