In eastern Switzerland near Liechtenstein, the Braunwald im Glamerland ski area has 11 pistes totaling 32km served by eight lifts with a maximum vertical descent of 600m. The scenic, car-free town of Braunwald is a great base.
Note: If you plan to head to Braunwald im Glamerland for snowboarding by train, here are two great options offered by the Swiss train system SBB. First, there is the discounted Swiss Transfer Ticket which provides a round-trip train ticket from an airport directly to the town near the ski area, plus 50% off any additional train or bus tickets. Second, there is the Snow-N-Rail ticket which provides a round-trip ticket from anywhere in Switzerland combines with a ski lift pass for as long as you need at a total 20% discount (see: http://www.sbb.ch/snownrail ).
Overall, Braunwald is the 43rd most popular snowboard & freeride destination of all 68 snowboarding resorts in Switzerland.