It may be fine for 40+ lbs., it depends on the stave, the moisture content, your patience in tillering, the final width, etc. I just finished an oak that was not nearly that long and it was pyramid and came in under 40 lbs. and it was no wider than that. So you have a real chance.
If it was a lefty I would say to work that knot down so it pokes out of the leather handle wrap and splits your fingers.....just for something different.
And I would say, no, to parallel; pyramid is the way to go.