I have to admit, the murder-mystery is intriguing, but a bit confusing for a Star Wars. I'm also not hot on the Sith being an organization made up of a bunch of Darths (IMHO one of the more disapointing aspects of the PT). It cheapens Vader's awesomeness.
I think the balance between keeping OT secrets and not is going to be very very tricky. Finding a way for the main character (Obi) to know the horrific fate of another main character (Anakin) but leave the audience in the dark will involve too many switcheroos and red herrings. At worst it might seem totally unsatisfying. If Anakin, one of the heroes, falls to evil, the audience needs to SEE it. I think leaving Anakin's fate and Vader's identity ambiguous might be the best way to go.
On the other hand, certain secrets, like keeping Yoda off camera, will be easy as pie.
I think cloaking devices and people being replaced with clones is a little to 'sci-fi' for Star Wars. Excepting the mere existence of the Death Star, technology plays an extremely limited role in the OT.
RANDOM THOUGHTS:
The Jedi are like gunslingers with white hats. They wander the galaxy, fixing wrongs, keepin' the peace. They meet up from time to time, expecially to discuss the training of young Jedis, but mainly do their own thing, often traveling in pairs, but not always.
The more I think on it, the more I think a Anankin-NotPadme-Bail Organa love triangle could be on the of the central spines of the NPT.
Palpatine doesn't have to be deceptive. Hitler was a wild, violent revolutionairy the entire time, people who liked him were just happy he was on their side. In times of crisis, a vicious old man with icewater in his veins may be just the sort of leader the peoples want. If he's plainly very aggressive, we can play him as a foil to Bail Organa.
The idea of galactic piracy has grown on me (although not Sith Pirates). It could form a good conflict, especially if the pirates are aliens, as that segueways into the Empires anti-alien policies. It would allow a sort of space-battle we haven't really seens. Medium sized ships blasting at eachother. Close quarter fighting deck to deck. It also opens the door for some cool minor characters, friends or foes.
One of the flaws of the PT was the constant repitition of the same planets. Naboo, Coruscant, Tatoine. I'd like to see some cool new planets. An underwater planet. A tropical archipeligo planet. A planet of gleaming quartz mountains. The only cool planets in the PT were Utapau (which we saw so little of) and Mustafar.