It might sound fatalistic, but I think that the lifespan of the game is a particularly relevant topic given recent releases.
Running out of New Ships
The expansions to the core game have come along smoothly so far, but there is a problem looming just over the horizon. It doesn't take a lot of investigation to realize that the pool of recognizable, faction appropriate ships available to the game developers has almost been dwindling. The imperials have a relative abundance of TIE variants, but the rebels have nearly exhausted their supply of ships. "Recognizable ships" have arguably already been depleted, with all the ships appearing in the OT already in the game. The simple fact is that FFG is printing ships faster than they are being created, there is a finite pool to draw on and many of the choices left are less than palatable.
Limited Design Space
In addition to the lack of usable models from literature and movie sources, the design space must also be getting crowded. As far as I can tell, the basic ship archetypes have been covered pretty thoroughly, and new ships would struggle to differentiate themselves from existing models. There is still some space left, but there is a limited number of variations you can reasonably expect from 4-stat ships, even with different action bars. It's tough to make a new ship that doesn't feel like one we already have. It is possible to refresh things with upgrade cards, but right now the primary delivery mechanism of those cards is with new ships.
Buying Time with Scum
I think that a major driving factor behind the introduction of the new S&V faction was a concern of the game's lifespan. The new faction opens up a little more design space with new upgrade slots, and a new design philosophy for the new faction. It has justifiable access to a lot of EU ships, some more recognizable than others, but many that would not feel right showing up in the Rebel or Imperial fleets. It's a blood transfusion for the game, and not a moment too soon.
But the original problem remains; the pace of releases is unsustainable. Unless a new approach to releases is adopted, such as the release of pilot/upgrade packs in lieu of brand-new ships, it's hard to see many more years left.
*edit*
I do expect that the game will continue to be fantastic until the end. But I have trouble seeing the game having the capacity to thrive past a certain point. I'd love to hear ideas on how it could, though!
Edited by Babaganoosh