FF15 will have multiple direct sequels according to Tetsuya Nomura, the game’s director.
He confirmed this in an interview with Famitsu, Nomura explained that the plan was to get Final Fantasy 15 to follow in the footsteps of FFX and FFXIII, by creating many direct sequels set in the same world.
When asked if fans would have to wait another eight years for another game, Tetsuya was quick to assure that this would not be the case. In fact, his response even suggests that any future sequels could be released episodically so that waiting times are as low as possible.
“As for as how it will be released, we’ll announce that later on; however, having you wait a long while for a next title isn’t something we would desire…” he said.
Below you can see an image of all of the characters that will be featuring in FFXV, and they seem to follow the more traditional, old school character design.