My experience with PPF is that it's best to do either all of the car or none of the car (or just a few tiny areas like behind the wheels, front bumper, etc).
With none of the car covered, the paint looks great and you can buy tons of touchup with the money you saved.
With all of the car covered, the paint looks a little dull but you never need to worry about it (so long as you remove the PPF every 5 years or so) and can lean on the car, park it under trees, let it be washed by any kid with a bucket and a dirty rag, etc.
But if you have large areas covered and large areas uncovered, it's the worst of both worlds: The covered areas will look a little different from the uncovered -- and the difference will increase over time -- and it'll be expensive, but you'll still have to baby the car because of all the uncovered paint.