I did not get the Hexamid tent, but the tarp--hence no mesh floor, etc.
What i was thinking though, was this. To sew some tent material that is cut into an elongated triangular shape, two of them.
At the wide base of the triangle, sew/bond one triangle to the outside edge of the front of the tarp.
The apex of the triangle goes inside of the tent. Do the same with the other piece on the opposite end of the tarp. Perhaps put some velcro on the apexs where they meet inside.
Sleep on inverted, meeting triangle floor. Saves weight in comparison to a full tent floor, but deflects some wind, but provides stability to the tarp while sleeping on same (shouldn't go flying off in the night since your weight will be holding it down too) and still allows enough ventilation.
Note, i would still put some "polycryo" underneath the mini floor. So, cuben mini floor may be viable. I do have a little 1 oz cuben left, but won't be enough.