"you must install in your ceiling is hardly a compelling solution." - why? we have "expensive" machinery to open our garage doors. Why specifically do you think it is not a compelling solution?
I personally think this is a great idea as ceilings are useless for the most part and that space can be used for something else - like storing the entire bed.
You can also put insulation on top of them to make your room more temperature efficient. Also prevents the need of dusting your roof joists, since they are effectively sealed.
I personally think this is a great idea as ceilings are useless for the most part and that space can be used for something else - like storing the entire bed.