Yes, there are really two questions here, one is, what is the appropriate main tag for these kinds of mountaineering routes (that can require rock climbing, ice climbing, crevasse rescue skills, …), and the other is, what tag should be used to indicate the difficulty. See also here.
I guess that’s a bit different from the sort of routes that have been discussed here, so if we want to discuss this further then maybe we should do so in a separate thread?