Most all of my modeling career has consisted of making really complex shapes using sheetmetal. Not until the past 6 months or so have I been really trying to make my modeling practices much more efficient using layout sketches and in-context relations.
I would like to post an example of one of my latest assemblies for some of you guys to pick through. One thing I do know is that there are almost always multiple ways of accomplishing the same end product in this software, so I would like to show you the techniques I have adapted and maybe someone out there will have a different solution. What I have done is created a 3D sketch to layout the basic shape, and used the geometry produced by it to drive the dimensions of various parts. Its not totally dialed in, but enough to get the basic idea across.