Just wanted to add that camping in crater is very doable. In fact, we did it a couple of years ago (three people team), everyone felt great, even sleeping was pretty decent, we had almost zero wind, and no penitentes. If my memory works, it was around early August. I wish we took time to explore ice caves, which I didn't know before existed, maybe another time. Check weather, wind, and assuming you have no issues with altitude it should be lots of fun. And be ready to see surprising faces of climbers coming up in the morning, it must be not very common to see a tent there (personally, I haven't seen one in my seven climbs). Maybe you can host them with hot tea or something :-)
