So, after a number of mantis reports that stem from this, and from some comments here on the forums, I'm thinking that it might be wise for the ilari to provide invulnerability from the cold in the chunks that they are in. Thus characters in a wind shelter node, settlement node, or underground neutral ilari cavern, would never have to worry about temperature. That way:
1. The various NPCs from other time periods that you invite to your settlement would retain their normal look and not don snowsuits.
2. Players who choose a player character without cold resistance won't die while trying to figure out what is going on. If they leave the starting chunk and go into a new ice age area, then start taking damage, they can figure out what's going and run away before they die, then craft a snowsuit.
3. There will be no way to functionally get killed through attrition while in the strategic map, citybuilding interface, crafting screens, etc, because those only occur in the presence of ilari.
The downside? Inevitable comments about people running around in shorts in the snow. That's the only one I can think of, and it seems slight compared to the rest.
Thoughts?