Check out using a marlin spike hitch with toggles. As you noted, the knot should bear the weight rather than the toggle. I made some toggles from a carbon fiber golf club shaft; some use aluminum arrow shafts. I prefer carabiners and use Camp Nano 'biners with MYOG 1/8" Amsteel Blue whoopie slings and 1"x8' polyester webbing tree straps from Arrowhead Equipment.
Making Garlington Insulators is a great way to insulate the bottom side of a hammock for light and cheap. See http://www.garlington.biz/Ray/HammockInsulator/Insulator.htm.
A Garlington Insulator is basically a light garbage bag with some sort of crumpled insulation inside and supported under the hammock with a fabric undercover. The undercover traps air as well and provides a wind break. The Insulators are simply placed in the undercover.
I made Insulators using cheap mylar space blankets and double stick tape to create a bag and then took more space blankets, crumpled them, and folded them loosely inside the space blanket bag. that gives me 2"+ loft and a couple ounces each. You can also crumple space blankets and put them inside a low density poly garbage bag.
I had a hoodless silnylon poncho made with drawstring channels on all four sides to use as an undercover with 1/8" shock cord in the channels. This pretty much clones the Hennessy SuperShelter concept and I use the Hennessy foam insulator with the poncho for warmer weather (I have a Hennessy Expedition). The poncho provides a wind break and protects from any side spray or bouncing rain that make it past my tarp. The poncho works well with an underquilt for extra warmth and weather protection. I get the weight back from multiple use as rain hear.
An undercover can be a simple rectangle of cloth with drawstring channels at each end. A cheap light hammock could be used as well. For testing and experimentation, you can just gather the ends of a painter's drop cloth or some polycryro window film with some light cord. The suspended weight is just a few ounces, so you don't need a lot of engineering. I do prefer having shock cord drawstrings in the sides as well as the ends to get the best seal. If you have a long backpacking style poncho, try it. It should be about the same length as your hammock-- at least past your head and feet. My hammock is asymmetrical and I added a couple toggles to tie it out to the asym spreaders. I didn't need any more tailoring than that.
2QZQ makes undercovers in silnylon or breathable ripstop for $35, which I think is a bargain. http://www.2qzqhammockhanger.com/hammockaccessories.html.