DD is 16 and our third trip is in April. She's more excited about this trip than the first two.
She isn't interested the fantasy Land rides anymore but is just as excited to see the Characters and most of the other rides. She's also planning the next trip.
There are a few car rental agencies at the hotels next to Downtown Disney. The rates are reasonable and we found it much easier to just take the bus to Downtown and walk across Hotel Plaza Blvd than to wait for a shuttle.