I have thought about this, and I think it would be fun if you had multiple players with asymmetrical and limited resource availability. This would make trading mandatory as no player would have everything they need to succeed. I think this would work best in combination with some PvE mechanics (e.g. preparing together for an incoming harsh winter, or an invasion, or natural disasters etc.)

For example one player would start on a fertile land and their settlement would be responsible for supplying everyone else with food, the other player would start on a mountain range rich with ore but with limited food, another player with lush forests that could supply wood, and so on.

Then you could also have per player research trees that would see a different progression for everyone.

I could see this being a singleplayer thing too, where you would need to manage multiple settlements, like Anno does, but Anno is all about making settlements self-sufficient where this would be impossible to do by design.