What is the largest sandbox setting you have run? Played?

How big before it becomes unwieldy?

Probably something Birthright.

I mean, yeah you can run some sci-fi and by sheer area it'll be larger, but realm management requires interaction with lots of "points of light" as it were. Just like Mass Effect can visit whole planetary systems and only a fuel depot or mineral deposit matters, actual physical measurements of space is more fungible in sandboxes. What matters is maintenance interactions.

That's why I say Birthright because, even though you delegate like a fiend, you have a larger regular cast that depends on your input. So in that sense it feels like a bigger sandbox because I need to supply more NPCs, locales, and spinning wheels. Basically as my players need to manage more, I need to juggle more in the air to keep the immersion going.

Unwieldy is easy to hit, but depends on the group (and their seasonal whims, apparently). I'm now at the point that unwieldy is trying to tear away a quorum of 2 or more players from their CCGs for an RPG lately. So I'm having a harder time trying to run a team caravan sandbox campaign within the distance of two towns than I am for running a governor solo realm management sandbox campaign. Somehow two towns and 8 main NPCs is harder for several players to keep with it than a whole province with 30+ NPCs for one player.

As for what's my limit on management? I honestly don't know. Given how things can be compartmentalized long enough to run a game for a few hours and then worked on for many long hours afterwards, I can't say. I guess it depends on how good you are with paperwork?

PS: Index cards are a godsend. A fantastic way to block off locales with actors. And since it's all cards, it's ready made for randomizing. Shuffle and fling something out there -- now dream up some hook. Even better, throw out a few cards in any layout and try to figure out "why?" interconnections.

The Wilderlands. It was pretty easy to do since all you need to manage at a single time is the close environment - you don't have to know the setting inside out to run functional, complex adventures. On the other hand, I have learned over multiple campaigns that one or two standard Wilderlands map regions are more than enough to accommodate as much play as you can squeeze into a campaign. You can actually get away with one unless your characters embark on some long journey or quest.