OK, I posed this question to a few OFBs (old flying buddies) , Old Timer Plane guys, ... First response from them all was "You don't fly on a day like that " !!!
Then we got into a discussion of balance , center of gravity , and all agreed that the lower the trailer is , the "apparently" wider (as compared to the height) area or "track", the more stable the tow would be ... Kinda' knew that already ...

Talked about shapes .... the Box was definitely Not the way to go ...all their ideas resembled the streamlined canopy off a P-51... Final conclusions... lower , wider , with the mass (weight) concentrated as low as possible (pendulum effect) , and fully rounded surfaces so the air would flow over it easily .. = More stable in the wind ! Makes sense to me ... especially the part about
not towing in very windy weather ...
