Ice by far! Such gorgeous attacks~
Froslass is my favorite Ice-Type. Elegant, fast, and a hard-hitter! I even fancied myself an Ice-Type Gym Leader for a while because of Froslass.
I also love Alolan Sandslash. I've thought Sandslash was really cool since the Gen. I days, super nostalgic, so I was pleasantly surprised to see it get an Ice-Type variant. It was also my most-desired Shiny in Sun/Moon, and by sheer chance happened to be my first (as Sandshrew)! If it wasn't for its awkward Sugimori stock, I imagine that it could've became my favorite Ice-Type.
I think I'd really enjoy using A-Sandslash with Slush Rush, but I'd also hate putting my noncompetitive Shiny A-Sandslash in the backseat...
Weavile is also pretty cool! And Lapras!