I have been using floorless shelters for about 10 years now. The Kifaru Sawtooth being my favorite. I like how fast I can set it up or take it down, tons of room, can wear my boots inside, flesh capes inside, enjoy the stove, stand to get dressed,, etc..... Bugs have not really been an issue, I keep my sleeping bag in a lightweight, waterproof, 4 oz bivy with bug screen. When ready to move out, I use the shelter to protect the items in my pack from the rain by stuffing the sawtooth into my pack and cover all the contents in the pack,, last in, first out.
Tarps and Cuben fiber works well too.