Hi Steve - well if the main body does not have very uniformly shaped profiles, then it does not tend to make a very good shape near the tips when you're trying to collapse things down to a single point. It's too easy for artifacts to be produced by shapes getting bunched up and squished together.

A lot of times if you're getting artifacts and fighting with stuff trying to make one single surface that is going through some significant changes in shape (like in your case near the tip you want something pretty different in shape than in the mid portion of the body), it's a sign that you're trying to do too much all in one single surface and you probably need to build it out of some separate pieces.

It could help though if you start to transform the shapes of the profiles to be more like a circle as they near the tip.

- Michael