Don't know if you ice climb, but 70m ropes are the sh%t when it comes to long ice routes.
I usually use double 60s for ice, but I can see a 70m for ice would be really fantastic. I am not going to run a 70 all the way out on rock because I need more pro than that. But on ice, your pro is spaced out so far, that I can see a real advantage on multi-pitch ice, especially if you are going to walk off and not rap, which is common on long ice routes.
I just graduated to 70m a few weeks ago after years on 50s and 60s. As previously pointed out, I'll add to the numbers that state "I don't think I'll ever go back". Don't cut it...not until you have to anyways. ;)