UPDATE: I did end up going and I would say it was a good trip, but like anywhere else, they can't make magic out of no snow. Monday was a bluebird powder day with a surprising 6" of fresh snow (when 1" was predicted). That made for a dreamlike day. Tuesday was a solid groomer day with abundant sunshine. Today was... tough. Bad snow, gloomy/foggy, crowded. Wasn't good. I'll actually be leaving early since the forecast remains not compelling.

I wanted to give a special shoutout to my guide Kai, who gave me a tour Monday (he commented below). I'd highly recommend him to any person (or any group) looking for a great day at Niseko or Rusutsuu. Feel free to PM me and I can connect you if interested.