Below is a chart I quickly prepared that shows the availability of the
movie-themed sets from TLG plus The Simpsons and Scooby
Doo. The reason I have included The Simpsons and Scooby Doo is that
they have larger sets associated with them. The hatched lines (and
titles) indicate these themes are associated with Disney. The years
indicate with colored blocks are those where a new set was released
for that respective theme (not that it was still available). For
obvious reasons, I did not include Star Wars-themed sets since they've
been consistently available since 1999.
Anyway, there almost
appears to be an exponential trend (based on this chart) that TLG is
picking steam regarding their use of licensed themes. My expectation from this trend is that there will be more to come from year to year.
If you include SW
(which was recently acquired from Lucas Films), a large percentage of
the TLG's licenses are/have been with Disney. So if you hear of any Disney
producing any big action/animated films or franchises, then you can
almost conclude Lego will want to get involved.
For example, Pixar (a
subsidiary of Disney) is supposed to be releasing "Incredibles 2" in
2017 and I wouldn't be surprised to see something from TLG since this movie is bound to be a big hit that year.
I think it's almost a certainty that Lego will release more Indiana Jones sets when the next round of movies starts getting released. They could almost just reuse the same molds. The same can be said for Pirates of the Caribbean 5, etc.
With the new Minions movie being released this summer, I almost wouldn't be surprised to see something here (although it's a little late in the game)...especially since Despicable Me 3 will be coming out in 2017.
Since a new Avatar trilogy is going to be released starting towards the end of 2017, that's another possibility (although I probably wouldn't be interested).
I would LOVE to see a Star Trek theme with a few UCS sets, but I'm not holding my breath.
Some other extremely long-shots may include:
How to Train Your Dragon (a franchise for Dreamworks)
Kung Fu Panda (another franchise for Dreamworks)
Planet of the Apes (probably too violent)
Wallace and Gromit (I would love to see this theme released almost as much as Star Trek, but not sure of its universal popularity)