I find Alolan Sandslash intriguing. Original Sandslash doesn't really stand out to me, owing mostly to its stats, but I saw Alolan Sandslash's increased defenses as a potential improvement. Plus, the Alolan form gets to keep the role of a Rapid Spin user. But of course, there's still one glaring problem: defensive ice types don't work. There is almost no additional type that will negate a couple of Ice's weaknesses without also resulting in some kind of 4x weakness, and Steel is no exception. Alolan Sandslash has several useful resistances, allowing it to come in safely and spin away hazards, but it also has 4x weaknesses to both Fire and Fighting, and the former is common as coverage for things that Ice/Steel resists. So, all this being said, I recommend a set similar to what standard Sandshrew ran in Gen 6:
Coldsteel the Hedgeheg (I'm so sorry)
Sandslash-Alola @ Life Orb / Lum Berry
Ability: Slush Rush
EVs/Nature: 252 Atk / 4 SpDef / 252 Spe, Jolly
- Rapid Spin / Swords Dance
- Icicle Crash
- Iron Head
In Gen 7, we have not yet gained access to a move tutor with Knock Off, so you'll be losing its utility and the ability to threaten spinblocking Ghost-types. However, Alolan Sandslash makes up for it with a newfound immunity to Toxic Spikes, allowing it to safely remove one of the easier means of threatening stall teams. However, if that's not your cup of tea, offensive variants are still fairly effective against slower teams, especially if you can clear out foes with Fire or Fighting-type moves before sending it out. In either case, the best way to use Alolan Sandslash will be to bring it in on something it can easily resist, which is not too hard given Ice/Steel's decent bank of resistances. Everything else here is pretty straightforward: max attack and speed plus Jolly for the best possible offensive presence, and an item that either boosts its power or removes status to prevent things like Will-o-Wisp from Ghosts crippling Sandslash. Only other options for this set might be Assault Vest for the spinner or maybe a Z-crystal for emergencies.
The risk I took was calculated, but man, am I bad at math.