So! Here's a bit of an update.

I ended up taking that $300 tent budget and buying an HMG Echo II insert . . . and then with a little bit of higher pay from a recent and unexpected raise stretched it a bit lot to pair it with an 8.5'x10' Cuben tarp. Big? Yes. But for that little weight I'd like to have that huge vestibule to sit and cook under on nasty days.

Mostly as a thought experiment, I'd like to make something like RayWay's batwing or HMG's beak to enclose the front vestibule. I don't know if or how much I'll use it, but I'd like to make it just in case I ever do want it. Any thoughts on design? I emailed RayWay to ask about adapting his batwing pattern for a pure rectangular tarp (his appears set up to go with an overhung tarp), but if that doesn't pan out, I'll be designing my own I guess and would appreciate any ideas.