Talking about it over on /r/AsheMains and it really makes me wonder. I feel like it'd be a super solid boost to AP Ashe/Support Ashe, even if the ratio wasn't crazy. I realize she's an AD champion traditionally, but she wouldn't be the first traditionally AD champion with some AP ratios (she's already got one on her ult) or even the first one with a functional AP build.
Her W is used to apply her passive so that your basic attacks are then empowered (based on AD, crit chance and IE)
I get that in lane it's used for poke, and you can get frostfang stacks with it if that's what you're trying to do, but the purpose of her W loses some of it's identity if you give it an AP ratio
Plus it doesn't fit her theme, her W is a very physical thing, a Volley of arrows
Enchanted Crystal Arrow will always be magical, magical=AP ratio
I wrote an AP Ashe (bot lane) guide a long time ago, back before runes reforged, Liandry's had Pen, Wits End had Pen, Guinsoos was totally different but
The guide is here: https://www.mobafire.com/league-of-legends/build/the-only-ap-ashe-build-513453
She's not a very useful support, has no CC until 6, and when you hit 6, your ult is very underwhelming in lane. Maybe it can create a successful gank, but often enemy support ultimates will provide far more than your ultimate at that time
I'd probably aim to get that^ as AP Ashe now, with fleet footwork probably
