Think I could like this a lot, I always love objects with multiple purposes. This could be a nice item to have in an emergency.
This may be a strange question, and I do not have the experience to know if it is a good idea, but could it be made with the top ripstop and the bottom silnylon? My thought is I could attempt to fold it (or snaps/fasteners) and use it as a pack cover. It could be a small tarp, it might even be able to afford some uq protection. I've never used a bivy, so I don't know if there is a breathable-vs-wet conflict. I am also pretty tall so gear or my daughter would probably fill it unless it was an emergency.
Again, love the idea.