"Without main quest you won't be able to do literally the thing your character is designed to do, but it doesn't stop you from doing the thing your character is designed to do" - you somehow
"buy workers with money you don't have and magically cause them to do something that isn't even in the game, pay attention to a stat that isn't listed anywhere" - you somehow
"after some hard work they will do the thing that isn't affected by hard work" - you somehow
"you will be able to safely exit your city and hunt for the thing that you presumably already have by this point if anything you said is remotely true" - you somehow
100% guaranteed we did NOT play the same game.
I didn't try sandbox mode, but if it's that different from story mode, and story mode does not at all match the game's categories but sandbox does, story mode absolutely should not be an option.
Or maybe my download was corrupted somehow but still managed to run at less than maximum capacity, I dunno. But I can say for sure none of what you said exists in the game I played.