As long as you book directly with disney, they are great about adding any deals or adjusting your package price you get AFTER you've already booked.
If you cannot wait to book your trip, then here's what I would do...
#1. Book the BEST deal you can currently find.
#2. if you get a pin (I've never received a pin after I've already booked, but it may happen, as I have heard that it does) and that pin allows for a better deal than you've already booked, then call Disney with your travel info. and your pin code, they will adjust the price/package for you so you can use the better deal...BUT, I know that they only do it up to so many days prior to you leaving. Not sure about the number of days, I'm sure you can get that question answered pretty easily on this board!
#3. If the best package you can buy now is better, than don't do anything with the pin (if you get one)
Of course, you are never FOR SURE going to get a pin, it seems quite random!!! In the past I've had a pin, but didn't use it because the listed deals were much better or even the same. Right now, with Disney's 35% off hotel deal OR the option to have free dinning, I don't know that a pin is going to make the offer much better...because that is usually what the pin has allowed (FOR ME) in the past.
The last two pins I've received were for free dinning OR for 35% off hotels so they would be the exact same offers that are avail. right now to the public. I'm sure people have received all sorts of different deals, but everyone who is planning a vacation there has different deals that work for THEM, because of their situation. Some people don't want to stay on property, some people don't want dinning plan, some people will stay at a value resort, some won't...so that stuff all factors in when it comes to 'what's the best deal' at Disney.