Steve, yea I recall your full length top cover, it's badass. It's also pretty advanced lol! I've got some hours logged at the sewing machine and I'd even shy from that.
I was just going on what you said about how this could be made so easily as an 'indoor' full length cover.
Anyway, the pic you posted on just covering the torso is what I had envisioned when you first described. I think draping over the ridgeline like Nest suggested might save a little weight vs. the velcro. Or perhaps using those bra clips.
This could be taken a step further for those who like pads. Take what you've got and continue all the way around so it has a bottom. That bottom could be a pad sleeve. This could also be done with a full length indoor cover and would eliminate the need for a double bottom. Not sure how that would feel though.....but I'd bet it would use less material than a double bottom. It definitely would if you just did the torso 'cocoon.'
Anyway, I like where this is going.....nice work!