Probably a muzzleloader or a lighter pack, an upgraded rangefinder that reads longer distances, more time to hunt...I can think of a pretty good list.
On the higher end, after spending some time riding around with CC in his Rhino side-by-side and enjoying his converted snowmobile box trailer that he has turned into a full-out camping unit, Rhino hauler and sleeping quarters with a heater that keeps things reasonably comfortable when the night-time temps get into single digits, either one of those would be pretty sweet too.