Great list! My favorites are definitely Phendrana Drifts, Castle Cainhurst, Valaak Mountain, and Freezeflame Galaxy. Some other more obscure ice levels would be Blizzard Peaks from Dragon Quest 8, Kingdom's Edge in Hollow Knight (if you consider it a snowy area), pretty much most of Sekiro's setting, Snowpeak ruins in Twilight Princess. Winters in Earthbound, especially for the music, Tantal in XC2 for the music at nighttime is especially amazing. Pikmin 2's Valley of Repose is nice too, and of course a majority of Celeste's setting is very well done also. We definitely had a lot in common, but I also like Snowman's Land in Mario 64, and I like Prime 3's Ice Bryyo for how unsettling it is with the odd transmissions that come in while in the area. Those are just a handful of winter/snowy areas I really like in games.