In another dev blog or somewhere, I recall reading that Geomancy/ Earth Magic ended up not being put in yet, and the skill ideas mostly went to Ice Magic. The Ice Magic armor buff is def. one of them, and I think Tuefax's idea would fit right in.

Another idea for Freeze Solid-- if it was a root as well as a mez, that would be something! Balance wise would probably call for the damage of the skill to be cut in half, but it really would be a much nicer debuff.