I have an HH Expedition side zip and a WL Snipe. I'm 6' or so and I find the HH a little confining. I'm a side sleeper as well and find that I can't sleep comfortably on my side in the HH, but can in the Snipe. I just can't get as flat in the HH as the Snipe. It is definitely a length thing.
I still prefer to sleep on my back in a hammock and am getting more used to it. In fact, the more I sleep on my back in the hammock the more I do on a mattress.