We also try to stay at a different hotel every time (my dd10 and I, husband stays home). We also try to do a different "extra" each trip during the middle of our stay to get a day away from the parks - last year it was Typhoon Lagoon. This year it might be the mini-golf - thanks for the suggestions!
This year though it is a total girl's trip, my mom, aunt, sister, niece, myself and daughter. I have been buying Disney pins on the Disney e-bay auction for the past few weeks. I am going to give each person their own "special" pin which has their favorite character on it, when we are on the plane on the way down to get the excitement started.
Also, as I am the one who was given the task of making all arrangements, we have a couple special surprises such as the Wishes cruise and a character breakfast at Chef Mickey's that I am not telling them about until it is time for the event.
Another way to keep it fun, especially, with a child is Pal Mickey. We bought one last year for my dd and it kept her entertained the whole trip. He talked the whole time in AK about each of the animals which she loved!
Another thing I am planning to do, thanks to one of the threads here is pull on the umbrella in MGM, pull on the rope outside of Indy Stunt Show, try to wake up Tinkerbell, and

look for hidden mickeys!