The only thing I could see ice useful for would be the minimize cooldown times on high heat high eu/t reactors or to turn a lowish heat mark 3 into a (barely) mark 2.
That being said, ice is irritating to make without using TMI or having some crazy BC+EE factory set up(which would change the game on reactors anyway) Using a stack to extend my meltdown a few extra minutes isn't worth it currently.
It might be usefull to generate more eu over a longer period of time if we used ice to shorten cooldown times on mark 2's, or even get us higher efficiency by turning mark 3's into safer mark 2-suc reactors.
Ice might have practical uses, I hate making it, so im not an expert on ice cooled reactors at all.