Alolan Ninetales: B- to B
Yeah, I think A Tales is due for a raise. In itself, it holds much more utility than just being your typical weather setter / play style lead. While, yes Alolan Ninetales literally carries Aurora Veil Offense on its back, this mon has really solid utility for a Pokemon that does lead such a potent offensive style. Encore is a complete blessing for it, and it stops many set up sweepers right in their tracks, and also in general disrupts offensive and defensive threats to the play style, but what am I doing, that is something you already know, so there has to be something in meta game trends leads to this rise.
That answer lies in the play style it leads itself, which I feel has really picked up its effectiveness in the current meta game. First, there is the rise of Rain, typically manned by Rain Sweepers such as Kingdra and Mega Pert, A Tales not only has the ability to beat those sweepers, but also to shut down Rain has a play style. Typically, while Alolan Ninetales does have to get a free switch in to those, A Veil can often afford to sack something. Klefki is also rather ill fated vs Aurora Veil teams, with a staple such as Xurkitree turning it into complete set up fodder with the ZHypno set.
To illustrate why Alolan Ninetales must rise, we must see what has changed in the meta for it. First off, it does like how scarf Lati is so popular regardless, that is a free Aurora Veil up, and it can ensue to encore it into something like Defog, which creates set up opportunities for the team, even if the Veil is then gone. Second, it is a solid answer to Weavile, which has risen in popularity as of late, and the bulky waters that have been on the rise, such as Jellicent, Suicune, Empoleon, and Mantine, are either prone to getting weakened by Alolan Ninetales or turn themselves into complete set up bait for the rest of the team. Ninetales finds it very easy in this meta to allow its teammates set up opportunities. Something I have liked using on A Veil teams is Gliscor, because it is such a nice blanket check to the playstyle's weaknesses and still gives the team rocks, and as such helps Ninetales with its rather ailing weaknesses. But, with the rise of all these bulky waters, Ninetales can pretty easily get up Aurora Veil and still weaken or create set up opportunities. This mon offers incredible support in this meta and its really worth noting how well it performs just in general. The speed tier it hits also easily allows it to outpace a lot of the meta and easily set up Aurora Veil, making it very ideal, especially in the current meta game. Its defensive utility is pretty underrated, even though Ice-Fairy is pretty bad typing on paper, it offers a really nice immunity in Dragon, which is always nice to make Hydreigon or Lati think twice. It has extremely solid Sp Def and in this meta I cannot stress how useful that is, with it being able to usually at least eat up a Xurk T Bolt, easily eating up Lati's hits and more, it offers more utility on the defensive side than one would think.
I think A Veil has become so strong in the meta game with Xurkitree and Hawlucha notably, but I think the main thing that creates a perfect trio is A Tales. I could argue for a Hawlucha rise as well, as that thing really just takes advantage of A Tales's support and can sweep way easier than it should.
Overall, Aurora Veil Offense has become really strong, and Alolan Ninetales should absolutely not just because of the solid rise of A Veil, but also because of its ability to dunk on rain, defensive utility, and overall ability to find ways to aid its teammates in set up opportunities. In the meta it finds doing just that easier than ever, and with the aid of some teammates, it easily carries a potent play style and makes it strong.
TL;DR: A Veil Offense has rose and A Tales finds it much easier to help its teammates find set up opportunities in this meta.
And do strongly consider Hawlucha to B, that thing is pretty amazing.