They have been trying hard in a number of areas and it would have been quite difficult to carry everything the way it was. They considered the possibilities with the new-generation hardware and the elements that need to BE included in XV.
According to him, it was troublesome to determine what was essential for the story which needs to be included in one title. The people who were involved where quite sensitive while dealing with this and debates were held numerous times. Even then, a definite answer was not found.
However, in the end, the developers decided to be as faithful as possible to Nojima’s story for versus and decided to stress on understanding the original story as much as they could. Meanwhile, Stella was included to play as the heroine in FFXV’s story, in order to play opposite Noctis in Versus XIII. However, in the end, it became increasingly difficult to include her as a character with role in FFXV.