I like your third option. Tent that fits inside the closet...I have had every option you mentioned... the tent I have now fits perfectly in a bedroom closet. I had to rig the ventilation into the walls and ceiling around the tent, but it is more stealth then any other options (NO light leaks whatsoever). Just my 2 cents
That said, i think I did get lucky with finding a tent that was perfect size...it was so perfect I had to build the tent inside closet. I am not sure if there is a standard closet size, but it was like they were made for each other