Complex sentence: Lucas felt that the film would portray visually foreign worlds, but that the musical score would give the audience an emotional familiarity; he wanted a grand musical sound for "Star Wars", with leitmotifs to provide distinction.
Split into simpler sentences: Lucas felt that the film would portray visually foreign worlds, but that the musical score would give the audience an emotional familiarity. Lucas wanted a grand musical sound for "Star Wars", with leitmotifs to provide distinction.