Dipping back in their history for a moment, he pointed to Final Fantasy 10-2 as the point where Square Enix started thinking about multiple games in the same universe--i.e. expanding the overall mythology of one particular entry, such as Final Fantasy 10.
And while Final Fantasy 10-2 basically inherited the qualities of the one prior, that approach toward multiple entries has now widened to crafting games with very different sorts of play mechanics within the same mythology. One such example, Dirge of Cerberus: Final Fantasy 7, abandoned RPG elements for third-person shooting.
With Final Fantasy 13, the design of the game became what the team refers to as "cut scene-driven" game design. A formula was distilled for the interval of placing the cut scenes between battles, the idea being that this maintains the rhythm of the game and keeps the player motivated to move through it. As a result, development was stretched by the considerable time required to generate all of the various cut scenes.
For the next game under the Final Fantasy 13 umbrella--two other FF13-branded titles, Versus and Agito were announced in conjunction with plain old Final Fantasy 13--Toriyama said that will not be the case. The focus will shift more to the gameplay.
Beyond that, he noted the pressures to create more open world style play by way of comparison to Western RPGs. While acknowledging that there is a greater sense of freedom in that style, he doesn't see it as the right fit for the story-centric approach of Final Fantasy. And though themes, locations, and game systems will undoubtedly change, the overall franchise will continue to focus on magnificent stories and characters.