I've considered this idea as well. I've seen some smaller geodesic play structures in plastic tubing. For younger kids obviously but wondered if it would be feasible to use one as the frame for a lightweight dome.
I reckon its workable with some DIY skills. I'd love to get even another 300-400 mm height in my Ob Shed to give me some clearance and allow a better balance position for the scope and better wind and dew protection.
It would also look real cool
