Mine would have to be:
SkyUI
Unofficial Patch
Simply Knock
SMIM
Blended Roads
My only complaint about the SPID version of Wet & Cold is that the author also chose to rip out all the AI features, where NPCs come in out of the rain. I recently tried to recreate the full W&C experience with a collection of smaller mods, and I couldn’t find anything to recreate that behavior. It’s the kind of thing that will make me figure out how to write AI packages some day.
I think the popular AI overhauls might allow the NPC characters to do that, at least AI Overhaul (https://www.nexusmods.com/skyrimspecialedition/mods/21654) says that it gives AI weather behavior, so maybe that could help you!