I visited Furano last christmas and have just booked again for this year...I LOVE THIS PLACE.
I wouldn't class myself as the best rider in the world but I have been to many resorts in Gunma, Nigata, Nagano, Tochigi, Fukushima and Hokkaido in 9 years of riding in Japan and out of every resort I have I have ever been to FURANO rocks!
There are some great powder courses in Furano which, after a heavy snowfall, provide great powder skiing. These areas are not groomed during the night and hence allow skiers to get a great powder experience first thing in the morning after fresh snow has fallen.
If you dont like the fact that theres no off piste... look into taking a day trip to Kurodake.