Hi jki, right now you're basically trying too hard to control every aspect of the shape directly.

You need to let either Fillets or Blend do some of the work for you, and doing that means that you won't directly model every single piece with your own curves. Instead try to have the pieces that you build directly be only for larger surfaces that have more of a single kind of shaping within them. When there is a portion of the object that is more tightly curved, that's a sign of an area that is in transition in between some of the broader shapes - don't model those transition areas directly, those are the ones that you want to have generated by filleting or sometimes by doing Blend.

In your case the transition area is in this region here:




Your main broad surfaces are like this:






Right now you've got so focused on building the transition areas directly that you're interrupting the broad forms and those are getting build in multiple separate stages - instead you want those broad forms to be one single larger surface that initially extends out a ways. As you've been seeing already, it's easier to build a smooth surface when it's done all in one single go.

Then those broad extended pieces can be intersected with each other and then filleted, or there is also a surface/surface fillet mechanism that can fillet between them directly.

A fillet or a blend is the main mechanism to generate something that's smooth to the surrounding areas.

You will also tend to get higher quality surfaces when each surface is not trying to do quite so many changes in shape within one single surfacing pass. When there's a change in shape especially when it's an area that is tightly curved, that is usually a sign that a fillet would be good to put in that area. Sometimes it's difficult to initially see where these should go since there is a natural tendency to draw every aspect of the shape. But you are seeing here the difficulties with trying to do the same work as fillets or blends directly.

- Michael