Simple answer: By not STICKING TO THE SAME CONSTANT STORYLINE AND INTRODUCING SOME VARIABILITY IN THE UNIVERSE AS WAS PRESENT IN THE ORIGINAL CONCEPT. BY NOT SHOEHORNING IN EVERY NECESSARY PLOT POINT TO NEATLY WRAP UP THE STORYLINES IN ONE NEAT LITTLE PACKAGE COMPLETE WITH PINK BOW. BY NOT STICKING TO THE INCREASINGLY RESTRICTIVE "SAGA" NOTION.
End rant....I feel a bit better now....Not so....maybe I lie. ;)