Using three (four?) PICs, a keyboard encoder, a 555, and four digital potentiometers when only the PIC16F747 would do is not a good design. I suspect everything on the "Light Dimmer Circuit" sheet could also be incorporated into the one PIC16F747.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.