FrankerZAustria and Italy offer the best value for your money in the alps. I would not even concider switzerland if you're traveling on a budget.
December is quite a risky time snow wise. Last christmas there was almost no natural snow anywhere in the alps whereas 2 years ago I was skiing waist deep powder in lech. In the early season the snow levels vary alot in different areas of the alps depending on where the first big storms head to.
The most snow sure resorts are located in the main alpine ridge. Id keep an eye on resorts like sölden, obergurgl, pitztal and st. Anton. In the early season i would avoid the smaller mountains around eastern and southern Alps.
Also the big french resorts could be an option but I highly recommend going to austria. You have top class skiing, great roads and trains, food and beer with half the price of switzerland.
If freeriding and powder interests you, go to st. Anton. It's a massive resort with decent nightlife and fairly cheap accomodation if you know where to stay. I go there every winter so I can give you more info about the resort if you want to.
i agree on everything except keep in mind that most of the glacier based austrian resorts don't have much if anything at the bottom, definitely not the nightlife he was asking for. St Anton i usually found to be too low down to be worth a visit early in the season, and also keep in mind he said beginner/intermediate runs not freeride
that being said i LOVE skiing austria, it by far has the best early season skiing, but the nightlife at the base of the resorts is usually lackluster, which is why i recommended staying in innsbruck