Naoki Yoshida: I’d like to refrain from giving away too many specifics at this time, but I think the chances of doing large-scale, challenging content is greater than creating high-difficulty content meant for smaller groups. It’s not that we are unable to create high-difficulty content for small groups, but currently I am a bit more hesitant with that direction overall.
In the case of a four-player high-difficulty dungeon, there is much less room for players to work with when it comes to party deaths or mistakes. If even a single party member is incapacitated or makes a mistake, it will invariably lead to a wipe, with not much leeway to save the run or come up with a creative solution. Another major reason is because our community continues to grow—naturally this is bringing in many casual players, and I believe that when looking at the bigger pictures, large-scale content will be easier for all players to get into.
If anything, one possibility might be high-difficulty floor(s) of the Deep Dungeon series… but please stay tuned for future announcements!