The more I think about it, I don't believe Lucas intended to make ROTJ the way he did when he was setting it up in ESB. The whole concept of there being 'another' - I don't believe it was going to be Leia originally. This would help to explain all the incest-esque occurences pre-ROTJ. I believe that either Luke was going to find another sibling, or another Force-adept, or that perhaps Luke would fail, and it would be left to this 'Other' to either help Luke, or succeed where he failed.

In short, I think Lucas wanted to end the Trilogy, instead of creating more episodes in his set of 'serials'. He tied up so many loose ends that could have been developed further:

- making Leia the 'Other'.
- making Leia Luke's sister, instead of having Han die and their relationship develop.
- having Yoda die, instead of furthering his training
- Vader's plan to overthrow the Emperor was not developed
- Lando just being forgiven without really redeeming himself with some valiant deed beforehand (just a casual reference to the stunt he pulled at the Battle of Tanaab) - perhaps having him sacrifice himself in a warrior's death for atonement?
- Of course, we all know that the Ewoks were used instead of the Wookies

And of course the Second Death Star was a bit of a cop-out, but I have a feeling that GL always intended to put the Death Star at the end of the story - and that he brought it forward to ANH because he had no guarantee of any sequels.

Was it ever meant to be a Trilogy, or was there meant to be more? What do you guys think?