Instead of the tube tent, or just a tarp -

Consider 3 surplus ponchos, one each. 2 ponchos snapped together make a 3 man hootch - if you sleep sideways. The third poncho becomes the floor.

Even better, the poncho can be used for catching rain, a stretcher, sleeping bag, sunshade, to sit on wet ground, a poncho (wow, what a concept) and more. The new ones are nylon and don't weigh all that much.

Spent many a night out under a poncho hootch, to include Alaska and the Sinai.