That looks interesting for other purposes I'd like to try. I love builds that let gravity do the work.
I have been wanting to try it again using a swivel in the line to allow the balloon to spin freely, but then use a tail/fin type of attachment to keep the rig oriented. It seems like anything would have to make it better.
More details here: https://en.m.wikipedia.org/wiki/Kite_aerial_photography#Pica...