I've used mine quite a lot now, for up to a week at a time. I've learned to pitch it as an oval instead of a circle in order to be able to stretch out in it, and also to angle the pole so that I don't have to curl around it. I sleep well in it because it's so dark inside.
Ventilation is critical or moisture condenses inside. I leave the entrance mostly unbuttoned and just hook both bottoms over the same tent stake when I want it closed. A fire in front makes it really cozy, but a reflector is essential in order to redirect smoke. Making the fire against a big rock and then pitching the tent with the entrance one big step away is ideal.
The only "modification" I've done is loops of baling twine through the grommets at the bottom. They allow me to use large stakes cut on site and/or tie off to saplings. It also adds some ventilation from underneath.