Eclipse Visual Editor is pretty dull in my experience. I had more luck with JBuilder, which is also based on Eclipse, simply adding a few plugins to it as many other commercial products do. It is still not able to parse any Swing code (I doubt any Swing WISIWYG editor does), but if you start with it, it gives you relatively seamless experience.
You need to pay for it though.
At the end of the day, I have worked with different similar UI tools, Flash Builder, Delphi etc., but unless you do some relatively trivial UI design, not including much business logic and communication with other layers, you'll have to accept that what you are capable of creating in code once you learn to do it properly is much more powerful than what any editor is capable of providing you with.
