I had an interesting idea of resurrecting an article that I modeled for in Prevention Magazine... lemme dig it out, scan and post a link.
Have you ever thought to do all over body workout circuit every other day? Or doing upper buddy day one, lower body day two, cardio day three, off day four and repeating cycle? Lots of different ways to mix it up. Is what I am trying to say. Once you have a variety of different movements in your repetoire you will be able to constantly keep your progress moving up as your body never really has too much time to adjust.
Just some out-loud thinking.
Not standard body-building training, but I think this approach may be helpfull for you to reach YOUR goal.