Just a couple of thoughts:
The Barnstormer may not be open until 10 a.m., with the rest of Toontown. And I'd do Astro Orbiters before anything else in Tomorrowland, as you can FASTPASS Buzz or Space, but not the Orbiters. That's an exceedingly slow-loading, low capacity attraction.
Solotraveler's plan is probably better, but I'd switch PhilharMagic with the Barnstormer if nothing else.
Sincerely,
Len