I just heard about a trick where you make toe covers out of tin foil to put over your socks, &/or under a thicker pair.
Its supposed to reflect the cold while you ride, & keep your warm parts warm.

My neoprene shoe covers do the trick, but my shoes have vents on the toes, so in very cold weather the cold finds a way in sometimes.

I bought some winter cycling gloves, I find they don't breathe very well. They're damp by the time I get to work.