"just to be clear you are saying to just sew a second layer of 1.1 below my hammock body big enough to hold my pad? so there will be stitching in the middle of my hammock body, any issues with that?"
I don't recommend it as much as suggest it as an avenue of experimentation. Sewing through the main hammock body may be a bad idea if it weakens the "skin."
I've done a lot of fiddling with hammock insulation schemes, mostly based on using an undercover. My primary undercover is also a poncho, getting back some of the weight in multiple use. You could adapt just about any poncho for use as an undercover.
My current light/summer scheme is a Hennessy SuperShelter open cell foam pad with a space blanket and an undercover. For colder weather, I use a shorter underquilt along with the undercover and space blanket which gives helps reduce the impact of any gaps as well as giving extra rain protection and a windproof layer, exactly like adding a rain shell to your layered clothing.
My personal gripe with the state of current hammock design in the complexity and fiddle factor of the insulation systems. We started with plain fabric hammock bodies made for hot summer backyard naps and started adding tarps, insulation and bug nets to get workable camping shelters. That has created some rather stuck-together designs with a lot of lines and parts and as we know in the UL world, that equals weight.
Ultimately, I think we need a hammock body with baffled insulation sewn to the bottom layer, an integrated bug net and ridge line and a separate tarp. Of course that means the customer staring into the face of a $300 or so price before the tarp is added.
The usual hammock buying trap is starting by getting a hammock and assuming "oh, I'll just use my pad," which leads into a long session of nickle and dime-ing yourself into a contraption that is makeshift, fussy, heavy, expensive, and looks like a backyard laundry line.
The cure is to start over now that we know we want to drag this into the woods and design to that point. We know we are going to need insulation for camping in most of North America for temps anywhere below the mid-60F and will need bug protection and a rain tarp.
Another UL design that comes to mind is to create a bivy hammock. That would have the sewn-in synthetic insulation with a waterproof/breathable outer shell or perhaps waterproof side panels with a breathable center section on an asymmetrical hammock body, a ridgeline style top side (a la Hennessy) with a vented Cuben or silnylon cover and integrated bug screen. That top cover would slightly overlap the sides to channel rain water past the seam and entry zipper, just like the storm flap on a rain jacket. The top should be able to unzip and roll down for warm weather ventilation. The bottom cover could be made with an expandable section so winter insulation could be added. Suspension would be just tree straps, carabiners and whoopie slings so setup would be simply wrapping the tree straps and clipping in: no guylines, stakes, underquilt rigging, etc, etc. Topside insulation would be a conventional sleeping bag or quilt.
Think this style hammock would be very weatherly in the wind and rain. We're talking about a five minute pitch, including tweaking for optimum sag.
