If they listen to the main criticisms we have here regarding Civ6 and think about resolving them in Civ7, then there's a great chance that Civ7 will be a really great game (not that Civ6 isn't already, it's already a great game, despite some problems we always point out here, but it could be a lot better).
In my opinion, they should pay special attention to AI and late game.
In my opinion, they should pay special attention to AI and late game.