There's still quite a few routes still not yet on sale. None of the Scandinavian routes are released yet as well as several others.
Salzburg and Turin both tend to get extra flights from December since they are ski routes, along with the addition of Grenoble. They tend to release Salzburg at the usual frequency (about 4x per week) initially then add extra flights when the ski flights are released. If you wish to fly between mid December and April, you may want to hang on until the full winter ski schedule is released, which could be a little bit later in the year, in order to get the best choice of flights.