Certainly the scripts (drafts) and the synopsis have many of the same characters and many of the general course of events are consistent throughout. In some respects retaining some of these things adds to the symbolic echoing of the Saga which occurs obviously later in the timeline - but many things would need to be altered. There are many character names throughout the drafts so I wouldn't think 'Luke' or 'Leia' would need to be retained - I had the idea of the 'trilogy' being titled as The Adventures of Kane Starkiller (maybe something alternate to 'Starkiller' however). The rest of the characters would remain somewhat the same in purpose to the story - however that is only because they are there because of the monomythic structure. I also plan on altering some things within the synopsis yet retaining the overall vibe - simply because, especially given that this was a synopsis, it needs some altering to make it a great "Star Wars" film.

Some things I may alter:

Make the 'general' an old Jedi on the planet Aquilae, who is the 'guardian of peace and justice' on that planet (it will be explained this policy was adopted by the Jedi a few generations prior and that it ultimately causes their near defeat during the war). This means its just the Princess and the two Imperial Bureaucrats who crash on the planet and are found by the 'Gandalf-like' Jedi.
Have the Jedi and his band battle a dragon on their trek to the spaceport, while their landspeeder is destroyed during the battle with the patrol (this means they have to travel over the mountains on foot)
Establish a Vader-like figure who at one point battles with the band on their trek.
Alter the Cantina scene slightly to make it less like A New Hope.
Change Yavin to another planet where the team crash-land. Here they will be captured by the Imperials, the Jedi is believed dead and will have to battle their way out.
The Ceremony at the end is essentially like A New Hope only the setting is much more like the staging ground seen for the Emperors entrance in Gladiator. The ceremony will induct the band into the Republic Elite Guard, whilst the Imperial Bureaucrats will ally with the Republic.
The Imperial-Sith Emperor will be added and the Vader-like figure will be one of his elite guard (the ANCIENT ORDER OF THE SITH LORDS is an ancient guard and aristocracy of the Empire which has returned to avenge their defeat many generations earlier - 25,000 BBY at the birth of the Republic)
Aquilae will be very much like Tibet with a progression (as they trek) more towards the Scottish Highlands and the New Zealand high alps. The designs will be wooden and anarchic however will be melded with technology (the temple/monastery will partly resemble a smaller wooden Jedi spire seen in the Prequels)
The band may be condensed with perhaps only Kane surviving.
Ophuchi will resemble a meld between Ancient Rome and Ralph McQuarrie's designs for Alderaan.
The Sith designs will be much more samurai-like and less science-fictiony as they are in the established in the EU.

The sequels will inevitably be about Kane Skywalker battling to defeat the Sith and save the Republic. Ultimately, at one point (and I know I may be in the minority with this) the Prophecy of the Chosen One will be mentioned. There will also be a Gandalf-like discussion between the Jedi and Kane - as mentioned above - where he explains that what matters is that peace is given to your time and that others will travel your journey again to stop evil - and perhaps destroy it once and for all (alluding to Luke's journey and the destruction of the Sith).

The actual film itself would begin (meaning Aquilae) on a planet like this: http://www.youtube.com/watch?v=KHGSwf15DJo, http://www.youtube.com/watch?v=b6hSK8CluxQ, and progress to, http://www.youtube.com/watch?v=g8g2vA9XwIQ and http://www.youtube.com/watch?v=8Pxl14Na3hE&feature=related (obviously 'Star Wars'ed' up)