I ended up going with a HMG Echo I tarp, the 25% sale they had going was too good to pass up. Now I'm spending my time looking for the perfect bivy. I'll also be adding a MLD Serenity Shelter eventually, and I sent him an e-mail about making a custom version with taller side panels, essentially making a giant bathtub floor. It was a no go (due to all the stock orders), but he said they'll redesigning the Serenity in spring along with adding a 2 man version.
I saw your Google doc. after I purchased my tarp, and I considered a lot of of those options. Nice to see it broke down in a chart. As you mentioned if it had every setup or different setups together it would be crazy, I have no doubt because I was mulling over everyp possible option I could think of in the same weight range.
So tarp and bivy for now, if I feel like I need more weather protection add a Echo beak after some trips, and see what the redesigned Serenity has to offer.