The Razorback is a good option is you want to spend more time in the snow and less time slugging up hill - typically the whole route is snow covered and the finish (ie, the base of the summit ridge) is at about the same altitude as the start (but it undulates a bit along the way).
On the summit ridge, I agree with Sabu - I'd stay away from the cornice and take care if it's icy, particularly if you don't have experience travelling on icy terrain.
If you are coming in along the Razorback, note that the ridge is exposed the whole way in and the weather can turn for the worse pretty quickly. It's not unheard of in winter to have effectively zero visibility along the ridge. A GPS or good navigational skills (and a compass and map) are essential (although it's not hard to navigate as it's essentially a north/south ridge).
Feathertop is a great trip in winter and a good introduction to snow camping, it just requires some decent warm and waterproof gear and an eye on the weather.