I would agree with changing out your pedals and going with platforms, and some type of rubber boots. Here in Montana we don't have rain in the winter, just sub-zero temps and cold winds...not sure which one is worse...lol. One old trick which works surprisingly well for warmth, is to put your foot in a plastic grocery bag, put the sock over that...or put the bag over your sock, either way. Sure your feet might sweat, and it might feel odd, but no one can see the bag, and if you change in a bathroom at work no one would know. Feet stay shockingly warm and dry. Here, when it gets really cold, I use snow boots and platform pedals.