Good call on the composites...stress and composites is a very sought after combination right now and will be for forseeable future. There is a huge shortage of US citizens with both.
Design is fun, but very few large companies allow their engineers to do both. Your either a puke designer or a stress weenie.
If you do choose a design-composites route be sure your using Catia v5. Us v4 loosers (users?) will soon be dinosaurs. As Island said, the CAD packages rotate quite frequently. It's best to get a few under your belt as that is one of the more important criteria for hiring. Companies do not want to spend the money to get you trained on "their" system. Catia, Pro-E, Cad-Key (ancient but still used), and SolidWorks are all good ones to know.
Don't get me started on contractors...we're the worst