Hi brash yes as others mentioned it would help a lot if you could post your 3DM files instead of only screenshots.

Often times putting in too many sections adds a kind of "pressure" onto the system which can make for undulations, using fewer profiles can help get smoother results.

Also from your screenshots it looks like there is fairly uneven spacing in some areas, try to make things a bit more evenly spaced instead of having one profile with pieces close to each other and then suddenly swinging far apart.

But if you could please post your model file it would make it a lot easier to experiment with it and give better suggestions.

- Michael