Calling it now: we'll have some Waves designed specifically after ships that appear in the upcoming films, along with the spin-off films, but if at some point things are too slow and we're scraping too low on the EU barrel...
We'll get new factions in the form of the Old Republic and the Confederation of Independent Systems.
But I see that being many, many years down the line. The EU is still rich with ships that can be added, and the new films/ongoing canon from other media will likely bring in plenty more. My only concern will be FFG's ability to make new ships interesting and have a "place" in gameplay, all while making efforts to keep things balanced... which they have. At the moment basically everything can be in a competitive list; even the lowly TIE Bomber (I'd say easily the least popular ship currently out) can be worked with, though it could really, really use the (apparently) upcoming ordnance overhaul to enter regular rotation among lists. But hey, it was just a wave ago that Y-Wings were considered some of the worst ships, and now look at those plucky little bastards. And the truth is, they were still pretty fun to play with even before they got the title and access to bombs. And to think, they're one of the ships most likely to benefit from a fix to ordnance!