I did a little playing around with balloon beds.
PIA as far as inflating balloons and getting them into the "bed."
2" dia balloons are impossible (for me and some others) to inflate without a pump.
3" balloons can be reinflated by mouth, so preinflating and releasing air is a possibility for short trips or special purposes.
2" balloons did not give me enough cushion.
More experimenting is needed to see if I can get comfortable at all. The balloons were too tight for a soft cushion in my quick attempts.
I might carry a balloon bed as a backup in case I am stranded in an airport or wish to use a shelter in a thunderstorm.
For a MYOG COMFORTABLE BED, I say, go HAMMOCK!