I always try for the last flight of the day/evening for going home. I treat it just as any other day, although on the last day I always have a funny feeling about having to go home.
As on any day, keep in mind that flitting from one park to another to get in one last ride here, one last photograph there, will consume a lot of time traveling. If you do this, don't actually expect to accomplish much.
Don't cut things too close for Magical Express. Aim to be back at your resort an hour before bus time, or 1-1/2 hours if you have to get back baggage from the bellhop. Less chance for anxiety. Chances are you won't actually get back to the resort that soon due to bus delays, last minute bathroom breaks, etc. My experience has been that bus service back from Downtown Disney is more erratic and/or spotty; if still true I can't understand why.
If your last activity would be a meal, consider doing that at the airport. This way you have more time for rides, etc. and even less anxiety about missing your plane. A request for an earlier (3-1/2 or even 4 hours in advance of flight) bus back to the airport is always granted when made the usual minimum one day in advance of checkout.
