Just to update everyone based on my original post, I have reserved a private car service for airport transport. Since we don't have TSA Pre-Check, we are requesting pick-up on our departure day for 2 1/2 hours prior to our flight. Considering someone on a popular Disney blog posted that her ME came today 4 1/2 hours prior to her scheduled flight, I'm pretty happy with that!!!
I was also told that IF the airport/ baggage check-in desk at the resort isn't too busy with ME guests, they would print out our boarding passes AND check our luggage at the resort, even though we aren't taking ME (of course, only for participating airlines, but ours does participate).