I think it is an excellent idea. However, especially when underway, there are a lot of forces in play. These will have to be accounted and provided for.
In a former life, we owned a Compact Jr. I made such a hammock for bedding storage in the pop top. It wasn't the most fashionable method of storage, but was a quick, easy way to get bedding out of the way. When the trailer was occupied, the hammock was pulled up tight to the pop top. When traveling, I would let it down and let it swing. This allowed the bedding to air out.
The structure of the pop top was entirely sufficient. I used through bolted hook eyes with large washers to spread the load. The cords that held it all up were sufficiently long to allow the hammock to swing, but had additional loops for hooking it up tight.
I have never seen a
Ventura, so don't know how something like this could be adapted. Probably the best bet would be to go down your list of friends and pick a nerdy mechanical engineering or civil engineering type; or if that fails, every engineer has had courses in mechanics. These guys just love to get their teeth into practical problems of this type.