It will do fine on 31's. 33's will definitely need a gear change. I wasn't thrilled with 3.73/31 combo so I installed 4.88's. Works very well, keeps rpms up where the little 2.4 makes the most power. Awesome creeping ratio off road as well.
Don't take lockers for granted. You can get stuck with them as well. Especially when your brain says, "You got lockers, go for it!" A winch is always a good to have, if not for you for someone else in trouble.
That's a good point plus a winch looks very cool, piece of mind, you can help someone else and you never know what your going to run into on the trail. Recently I came across a downed tree and I had a very difficult time chopping & dragging a portion of it out of the way. A winch would have been great.