>>32584226Ninetails is hands-and-feet better, but honestly, doubling down on your setter isn't a bad idea, especially with how frail they are.
I'd favor Abomasnow, since it can make decent use of a megastone, and otherwise can fill a noticeable physical gap that is emerging thus far, as well as run Leech Seed. It also lets you be more aggressive with Ninetails, since you are no longer hopelessly borked if you lose it.
Aurorus offers nothing Abomasnow and Ninetails together don't, and a 4x weaknes to Fighting and Steel is a bigger problem than a 4x to Fire and Flying. Abomasnow also resists ground, which is nice.
Ninetails
Abomasnow
Regice/Articuno
Avalugg
Heatran
Gliscor/Other
isn't looking too bad.
Remember, you can put Safety Goggles on someone to make 'em a de-facto "Hail" mon, with immunity to sleep powder as a free bonus.