What I'm about to tell you is NOT how Immigration wants things to be done and you should keep in mind that this is a single anecdotal episode about one particular individual and it may or may not work out the same for you or anyone else. Just keep that caveat in mind.
Last time I came back over here rather than bother with applying for a spouse visa from outside the country I just came on a tourist visa and applied for a change of status to a spouse visa after I was here. Immigration doesn't like it done that way, but there I was. When I went and applied for the change of status I asked the Immigration officer if I could go ahead and look for a job. The response was along the lines of, "You're not supposed to, but you have to eat." I had previously held a spouse visa, had been married for about 15 years, and we both knew that the paperwork was a formality and that there was no chance of a visa being denied under the circumstances and I would have it in a couple of weeks anyway. A large factor that separates a spouse visa from other categories is that ostensibly your purpose for being here (especially as a man...."bread winner") is to provide a livelihood for your Japanese citizen family members. Since the welfare of Japanese citizens are tied up in it, they don't get quite as uptight about it.
Also remember that your wife's green card will expire if she is absent from the U.S. for one year. Or at least that was the case the last time I checked, quite a few years ago. There is some sort of thing she can apply for which extends that for one year. As you no doubt know, applying for a green card can be its own brand of bureaucratic hell. So if you envision at some point returning to live in the U.S. with your wife you would be well advised to look into this aspect of the move very carefully and, if necessary and feasible, to have her pop back into the U.S. or a territory (Guam will do fine) prior to the green card expiring on her.
Meantime, bone up on Japanese like your life depended on it and DO NOT neglect expanding your reading skills. It is hard to feel like a grown-assed man with the dignity appertaining thereto when one is functionally illiterate.