IF it were to happen, which I don't think GL will ever do it, it would have to include some major new villian based on the Dark Side.
This of course is hard to visualize as Anakin kills off the Dark Side, so what you would require is this basic plot line.
1. Luke begins to rebuild the Jedi Order and its vast knowledge base from the ruins of decades previous.
2. One of his best students eventually begins to secretly toy with the Dark powers.
3. The first movie deals with rebuilding and the continued fight against the chaos that would naturally reign from the collapse of the Empire.
4. The second movie would deal with the final wars and full control of the new Senate/Dimplomatic Galactic order. While at the same time pivot a dark point where the Dark Side is officiall reborn with potentially a significant number of young Jedi's all lead by Luke's best pupil and the death of Leah.
5. The third movie would follow that new evil into a massive war where only one or two Sith were left after a brilliant defeat and Luke's own demise. This would end the full "Skywalker" storyline. But, leave open the potential for a new set of movies based on this questionable last Sith lord and the new rebuilt Jedi's with the support of a strong vibrant Galactic Government.
Didn't read full OP, will give new post below.
