'manageable world' is correct and usable in written English.
You could use it to refer to the idea that with the right efforts, the world can become a better, more manageable place for everyone. For example, "We need to work together to create a more manageable world for generations to come."
Our misshapen but manageable world suddenly imploded.
They are only a way of moving towards a more manageable world.
Sporting flip-flops and a T-shirt, her hair a bit wild, Nyasha is a natural beauty and an artist, the opposite of her older sister, who wears elegant brown boots and walks with purpose through what is, to her, a calculable and thus manageable world.
As I took the cure in my den recently, inhaling "Inkheart" by Ms. Funke and snubbing (with great relish) the insistent ring of the telephone, I realized that I'm trying to recreate that long-ago porch, trying to make my world manageable enough right now to wrap it about myself like a prayer shawl.
This ability to solve problems (at best) in a matter of minutes or (at worst) a matter of months has made my world manageable, restricting any anxiety to my field of vision.
It's the little things that make the harsh world manageable: the bus driver who waits for you, the professor that writes "Good job" on your assignment with a smiley face, or the cashier that asks you about your day.
Creating health services in nations where nothing works is a daunting task, but all of the steps are manageable if third-world leaders are committed to them and donor nations will provide enough money for long-term reform.
From the placid vantage of a laptop, the world looks manageable.
It allowed us to feel superior, it divided our world into manageable blocs.
There's a theme developing here… As a slightly scared child, I had a cataloguing gene, a way of making a complex world more manageable.
As the West moves away from its imperialist mission to create a "manageable" Middle East, the Arab world is also slowly moving away from broken systems, fabricated borders and debilitating dependencies.
