If you're all early risers, it's easy to get a nice, relaxing vacation in one week. I did it, and during the busiest time of the year, no less!
Plan on hitting the parks at opening, and leaving by noon. That is my best stategy, it works no matter what time of year you go. You'll get all the best of the best rides in, and have the entire remainder of the day for relaxing.
During busy times, make sure you have your ADRs in order. You can always drop one or two if you decide you don't want to keep them.
Leave 1 or 2 days open for other possibilities...water parks, mini golf, resort hopping, pool lounging, DTD shopping...whatever you like. Book ADRs and Cirque or HDDR/Luau for those days.
I never recommend the sleep-in, start late strategy for busy times of the year, though. You will always hit massive crowds coming into the parks late, who are planning on staying for the evening EMH/parade/fireworks. Massive crowds ALWAYS lead to stress, no matter how patient you are. You will see the worst of humanity in these crowds. Avoid them if possible, to preserve your serenity.
That being said, at slow times of the year, if you are sleep-in kind of people, make use of any late EMH being offered. I hear you can get lots of park time in at the tail end of these hours (I've never tried it myself, so this is only hearsay).