If you don't like Swing layout manager, the SWT layout engine closely mirrors Interface Builder's own layout engine.
BTW: if you think layout managers suck, try making a win32 gui that can handle different font / window sizes / dpi settings. Lotsa fun
But I still agree with you on one point: Swing UI can (and will) get ugly, if they are designed by someone who is not very intimate with the Swing (over?)use of Design Patterns. Just look at the source code, they are all there, all of them, I tell you, it's a very fine piece of (over)engineering...
So the perverse side effect is that, if you don't know each and every design choice, you end up using a subpart of swing and create a maintenance nightmare.
But if you are one of the few 'Gifted', you can create some wonderfully elegant and fast code. I met one such person, only once though...