That's because the only time they made him interesting was when Bruce Timm & Paul Dini were in on it. Even when they retconned their version into comic continuity it still only felt like a pale imitation.
Actually, I know that "Heart of Ice" is the fan favourite freeze episode (and for some, episode, period) but I really think the most interesting Freeze story was the Batman Beyond one. "Meltdown" I think it was called. If for nothing else than his crazy suit at the end.
Has anyone brought up DKR or DKSB yet? I know they can be a divisive set of books, but they are honestly among a very small number of comics that I can read more than once in a blue moon.