I love these shots! Film photos is like traveling in time. You go back to the past.

Double exposures sure are fun but what I've noticed is that they come out better if you either do not shoot the kind photos on top of each other that have sky in it or lots of sky and perhaps it's good to underexpose the photos too. But of course that also depends. Sometimes the best double exposures are the accidental ones. Though I love these what you got!