Wow, I never looked at the Ring of the Icy Soul before, but that has to be the worst item I've seen yet in D+D 3.5. It's really, really awful. Like 3d6, I would pay to get rid of the cold subtype, and they want a PC to pay 100,000 gp to gain it? Right...
I think what is going on in your campaign is probably fine, if not harmful to the character. Of course that evaluation comes from an "average" campaign mindset, where fire spells are common and cold environs are not. If your campaign is completely full of cold stuff and you don't ever see fire, then this may be a bit unfair.