I will add just a little to Spicey Cat's observations . . . . .
First, to say that if you're going any time after Labor Day, crowds will be smaller, and the end-of-day rush won't be as bad.
Second, everyone doesn't leave all at once on those days when there isn't a Spectromagic or a fireworks show. (Can't remember if they're doing fireworks every night for the 50th celebration) In that case, the rush wouldn't be so bad at closing.
Third, getting back to the TTC to get to the parking lot can be easier taking the boat rather than the monorail, as another option. But you'd still need to wait for the parking lot trams.
You have a benefit that Coronado Springs buses tend to be among the least crowded, because as a convention-oriented resort, they have a higher percentage of guests who aren't going to the parks, plus they don't share a bus with any other resort. But I would just be prepared for the *possibility* of waiting for possibly one extra bus, if the line at the MK bus depot is more than one bus-worth of people. If you're prepared for a little wait, you won't get stressed out, and there's a good possibility that you'll get on the first bus that shows up.
Even if you're thinking about driving to MK for your afternoon/evening visit, *definitely* take the bus over in the morning - trying to get from the parking lot to the gates for an early breakfast seating is just too complicated , with lots of things that could go wrong, depending on who happens to be working on a particular morning.
As for the other parks, I've never found car traffic to be a problem getting out of the lots at closing. From MGM and Epcot, just look for signs that say "Coronado Springs", "Animal Kingdom", or "All-Stars", and they will all take you in the direction you need to go.
Hope this is helpful.
