Another way to look at it is; In Emirates you will bring your family to DUB and then it's you off to "see" the rest of the world for perhaps an average 16-18 days a month, while the family is hanging around in DUB.
On the contracts in Japan you make some pretty good money (despite the low $), leave the family at home where they have friends, your wife has a job (?) etc and then you come home for 10 (?) days in a row each month. I think your days off are guaranteed to be rostered in a row so does not really matter where you live, its doable.
As an option if you are looking for something new you could take a look at China, lots of good contracts available now. You can get contracts in Beijing or Shanghai. Different experience in big modern cities, potentially jobs available for your wife, international schools for the kids, still relatively cheap to enjoy "western standard" of living, expanding market with good growth potential over the next 10+ years. Lots of direct entry commands available.
Good luck!
CP