Well, regardless of what your goals are, I can't imagine having complete workouts without using some isolation work. I wouldn't want to have a shoulder workout without some DB laterals. Or have a chest workout without some flys. Believe it or not, I didn't really start shaping my chest up until I started doing quality isolation work (superset incline DB flyes with incline DB presses, amazing for me). But I suppose that those same goals may determine how much isolation work you're actually doing. I would say that the bulk of your exercises should be compound because it just makes more sense. You're in the gym to train muscle. Compound exercises involve more muscles being used. Voila!
I have seen before where some people totally throw out all isolation work but I don't think those people's goals are to look as good as possible. Usually it seems that all they care about are big lifts. But I'm pretty sure that even competitive weightlifters and powerlifters still incorporate some isolation work into their routines.
If you want to do more of a bodybuilding routine where the focus is to build the body to look as good as possible, then definitely include isolation work.