Yes, I know it isn't going to happen, but if it was up to me, they should start in a completely different era to the end of ROTJ and use the existing material from the Expanded Universe. The EU doesn't get nearly as much love as it deserves and since there's so much cool stuff in it, it would be a waste not to use it! I for one actually prefer the EU content over that of the films.
It would be a complete cluster**** of information or lackthereof if they chose to adapt something from the EU, so much of it either requires the inclusion of other material for the purposes of exposition, or it just clashes with other material to the point where it's almost impossible to determine what is canon and what it not.
Ignoring all of the EU altogether and attempting to come up with an original story is their best option.