Hi Doug,

It would seem likes a quilt would be the way to go, as they have a broad temperature range at minimum weight and bulk. There aren't a whole lot of them available commercially compared to sleeping bags, but there are a few.

Otherwise, a 30-degree down bag with full zip would be a nice option. I can endure pretty much any summer Sierra weather surprises in a 30-degree bag, while my spouse needs something practically winter-rated no matter what. Down bags in this range are mearly always under two pounds, many closer to a pound. You'll never touch that Alps giant again.

Happy shopping,
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--Rick