I know what you mean. I like to board early, too. Yes, some people do take ME to the airport to catch an early
DCL bus to the port. That is a lot of bus riding for one morning, though.
An alternative would be to spend your last night before the cruise at the airport Hyatt. It's a very nice hotel with great rooms and food, and is typically cheaper than a Disney moderate. That way, you could take ME back to the airport the night before, and the morning of the cruise you would just walk from your hotel room to the DCL bus loading area. Easy peasy.
This is one reason why I prefer visiting WDW after the cruise, rather than before. They take their sweet time getting guests from the Disney resorts to the cruise ship.