I actually like to be in the parks until they kick us out the night before so we always play the last day by ear. Some times we just want to be lazy and never leave the resort, other times we try to get a little more park time in.. crowds really don't matter the last time, sometimes just 1 more snack and walking around is a better ending then sitting aroudn the resort and upset your leaving.
If I was planning a last day park where I needed to be waiting for magical express about 2:30pm, I would do this. Rope drop the park to get the lowest crowds, you don't have to rush the big rides and you'll know what your in the mood for by the time your starting there. Then do a ADR for lunch at the resort. The big kicker is I would also request a 1pm checkout after I'm at the resort (just call front desk from the room and ask for a 1pm check out time). 1pm is the latest you can get with it being free. This would allow us to enjoy the most of the park before the crowds get larger, freshen up and change before the flight because you still have the room so pack your carry ons accordingly and have a nice we did it family meal to relax and get into that travel home mode. If anything goes wrong, you could ditch the freshening up or lunch or cut it short but you'll be at the resort for your bus without the stress of will we make it on time that can happen when you cut a park day too close to your me bus.
Rope drop last day is a great time for disney snacks for breakfast and might even become a tradition on your future visits. I like gastons for this but ice cream for breakfast is memorable also.