Not usually considered...
but, I have an Austrailian Shepard and she lets me know when any humans come near my home and if they are at the door she lets them know that she knows they are there.
She's been a great watch dog and that's really the most important factor. She's medium sized and very friendly with family and friends, although she still lets me know even when they arrive!
Hope that helps.
I have been looking into a Norwegian Elkhound as well.