Shadows of the Empire, done in Clone Wars format since any attempt at physically replacing the beloved original cast would be viewed badly but there's tons of capable sound-alikes. It is enmeshed in the original trilogy so most uninitiated viewers will understand the context. It already has an amazing soundtrack and tons of art to start with, you could just build from there, bringing Gall Spaceport, Mos Eisley, the Bothan Colony and Xizor's Palace to life in beautiful detail.
That or the Thrawn Trilogy, but that one is so long that even three movies might not be enough- I swear Leia hops through like six planets trying to evade the Noghri in the first book alone.