A lot of whining about VIIR. Some old trauma or smth... I'm not in the subject 100%.

Anyway, to return from off-topic to the real topic of discussion. Assuming that Rebirth and Remake do not exist, then I would say that among the newest games in the series, XVI is the worst path forward, the worst foundation to build upon. This will sound spicy, since Barry really perverted people psyches here, but I would rather take XV as a basis and build the future of the series on its foundation. A full team of characters, great chemistry between them, an open world and exploration on various types of vehicles, a truly emotional story with the ending that made people cry and care (even according to the latest poll), a more distinct and memorable style instead of dull medieval slop. All you need to do is take, improve and partially rework the combat system, add depth to the mechanics, add interactivity to the world, more side activities and interesting mini-quests / mini-games, and you will get an ideal FF game. Well, and of course, you also need to give talented writers time to make a meaningful script for the game. XV didn't have that luxury, but it was still emotional, XVI had that luxury, but it ended up being the dullest pontification in the history of the series about the most obvious and stale topics.
We have to forget about XVI and come up with something new, or go back to XV and build the perfect Final Fantasy on it.