Hi, Jim - welcome back.
Since weight isn’t an issue, but space is, would a self-inflating pad or air mattress make more sense than a closed cell pad? You’d get more r-value for less volume. Since you’d be camping on snow, the r-value could be critical.
Also, what about a tool that would let you build a snow shelter? I’m from Ohio, so I have no real knowledge about snow shelters - but I’ve read that they work if you have time to build one.