"In every walk with nature one receives far more than he seeks". John Muir.
Sleep naked on nylon, you won't slip at all!
Most of us end up poorer here but richer for being here. Olddog, Fulltime hammocker, 365 nights a year.
Ill tell ya buddy, I've been hanging for 2 years now, hung many hammocks many times and its pretty rare I get the perfect angle. But in all actuality, the perfect angle is any angle that you sleep in comfort I always achieve that.
I think that using a line level sounds like a great idea! I'm going to try that out.
My Flickr photos Outdoors collection