This article talks about some tips for sleeping without a tent.
It always an awesome sight to see the beautiful wonders of the outdoors. Especially at night because if your sleeping outside you are able to see the awesome sounds and views that you wouldn't normally see with a roof or a tent blocking your sight! Although its risky because you aren't able to fully predict the weather, and are however, unprotected from wildlife and bugs. Its always smart to check the forecast before heading out and bringing a tent just in case even though they are quite weighty and space consuming. It will be well worth it if you get caught in a sudden storm.
There is pros and cons to sleeping outside but i deffinately think it is something worth trying atleast once in your life! Even if all doesnt go as planned, you will have stories to tell and pictures to show. Also, i'd bring bug spray, and a lot of it.