I have been to Avoriaz twice as an advanced skier and thoroughly enjoyed the wide open runs to properly carve turn, the views from the top of the lifts and the après at Foulie Douche.
The runs are long meaning as an experienced skier you spend more time skiing than on the lifts. Its great for beginners too, theres a wide range of runs, suiting all abilities, theres lots of things for childrens enjoyment (and us adults too), The Stash has small jumps, tree runs, and other fun things, its a long wide green run suitable for anyone, fun for all.
The only thing I would say thats a slight negative, is that, if the surrounding resorts in Portes Du Soleil dont have much snow, Avoriaz gets very busy and the lift queues can get very long. But thats usually over the side where The Stash and Foulie Douche are.
At a certain time the year (March I think), the Snowboxx festival is on, and the ticket price is included in your lift pass. A great way to have even more fun on an already fun-filled holiday.