The developers of upcoming Just Cause 3 have been talking about the game's world size, destruction and why the game needs a story.
In a recent interview with Game Informer, game director Roland Lesterlin said that the game might not be bigger than Just Cause 2 but it will be "denser."
Just Cause 2 was already enormous. We really wanted to focus now on density and the feel of the world itself. So we didn't necessarily just have to do increased land mass. But we have certainly gone a lot bigger when it comes to density of the world. And now it's not just on top of the world--we also have caves and tunnels and all sorts of stuff there, too.
On the destruction side of things, which lets face it, was the best part of Just Cause 2, destruction will have a much wider scale than it did previously. With the ability to do more than shoot holes in a wall, you could perhaps blow the bridge up you just crossed if you're in the middle of an intense chase.
Moving onto as to why the game has a story, it's because "everyone likes a good story" according to Avalanche co-founder Christofer Sundberg. When asked the same question, Lesterlin said that it serves as a back bone to tie everything together.
To finish off, Sundberg has said that Just Cause 3 will have a much more serious story that players will want to follow, diving into the past of the main character (Rico). The game still won't be story-driven though, as players can still expect a large amount of insanity.
No official release date has been confirmed for Just Cause 3 yet, other than a 2015 release.