I agree w/ days off. Personally, aside from our first trip (which was a nightmare) we never do more than 3 park days in a row. We take advantage of all the amenities at the resorts, as well as areas like the Boardwalk and DTD on "off days". They truly recharge us.
If you are staying onsite then look into fitting a few EMH (morning or evening) into your schedule. They will help allow you time to see popular attractions w/o the longer waits.
Also, don't forget to book a few PS's. As it's a good way to conserve time (don't have to wait around as a walk-up) and it's a good way to have a little down tiime.
I don't have a specific plan, as the time of year, EMH days, ect really play into the planning aspect.