This is more of a personal preference thing, but I've discovered that it's really easy to make very pleasing looking vector shapes by alternating between lowest curvature and highest curvature from point to point. Use the low-curvature points to set the "corners" of the shape and then you have a point between each corner you can use to totally control the curve of that line, without any side effects from nearby curves.
This just results in a kind of shape that I like. Again, just a personal opinion, but I'll be doing that often.
I also wrote something about using masks, but it's long, and it's on the laptop, and I'm not at home, so it'll have to wait 'til tomorrow.
Something I kinda like for shapes ...
Moderators: Víctor Paredes, Belgarath, slowtiger