Yeah, there's just nothing like it in nature that could be used as an excuse. In a reality-based world, the moniker "Mr Freeze" would have to be more about what he does rather than the literal "he's a frozen man" with a freeze gun and a frozen wife character.
But look, they managed to reinvent the Joker and hung his character on "Anarchy". Clearly, Mr Freeze needs to be 'cold' but maybe its just in his methods rather than all the nonsense about being a scientist, falling in a vat that made him cold, having to wear a special suit, keeping his wife frozen, liking diamonds because crooks call it 'ice', etc. Let all that stuff be the comic book stuff. Reinvent Freeze from the ground up. His gimmick can still be 'cold', like Ledger's gimmick was still a 'clown', but given Freeze something deeper to hang his character on (like Anarchy).
I suggest "Revenge", because it challenges Batman's vigilante aspects... and because, it's a dish best served... cold.