Since they're obviously going with the faction-adding route, this seems like the next logical step, and would follow with the LCG faction spread.
LCG has Imperial Navy, Rebel Alliance, Scum & Villainy (all present so far), then Sith, Jedi, and Smugglers & Spies.
And I imagine the new movies will add some craft usable by Sith and Jedi, so they'll have a lot of material to use by the time they feel a fourth faction is necessary. Then maybe they'll make people happy by Darth Vader's and Maarek Stele's conversion kit like they did with the Fett.