Theres a few things to do about snow that will also give you better traction in other places.
1.You could get front skis,but you said you would also be climbing and in grass and stuff so...
2.Take off the tires,put nails in tires pointing outwards and super glue them in.Put tires back on.
3.Get rid of the tires,take off your wheels and HAMMER nails through the outside of the rims.Put rims back on,leave tires off.

P.S.I Hate Revo's!THIS IS SAVAGE COUNTRY MAN!!!