I just ordered a 358 Cub from Passion Racing for trail/woods road type driving - I can't wait to get them.
Your 2:1 carb set up should give you a little more bottom end.
You definitly should have your crank welded and put a TZ bearing on it, a Coolhead would be good also. Call Passion and he'll tell you what you need/or should have
I bet it will be hard to keep the front-end down with the -2 swingarm on a 70+HP bike you'll have