Ooo, I think I may have found a location for my innocent Scorpion wife/gruff Crab husband/various intrigue idea!
Since the wife (I've decided to name her Umeko) would be joining the Crab clan, I figured they would be living within Crab territory, so I was looking around for the closest thing the Crab have to a prosperous city, and I think I've found it: Sunda Mizu Mura, or Clear Water Village!:http://l5r.wikia.com/wiki/Sunda_Mizu_Mura
It is one of the oldest settlements in Rokugan, as well as one of the largest trading centers of the Empire. Most of the trading is run by the Yasuki Family, so most Crane avoid them, but they do trade with ronin smugglers and non-Yasuki merchants. Though a city, Sunda Mizu Mura continues to call itself a village (mura). It is positioned on the River of Gold, which directly links to the Earthquake Fish Bay, and from there to the ocean. Lots of fresh seafood! And it's home to the oldest Crab dojo, the Sunda Mizu Dojo. I figure there would be a more refined section of the city for the samurai and higher-ups to live in, but there is also a red-light district for you naughty types. Crabs like to party hard, after all!
Anyway, since the Crab and Scorpion clans have formed an alliance based on guarding the Second Festering Pit which opened in Scorpion lands, I figure that many marriages have since happened between them to further cement it. So, hopefully, Umeko won't be the only Scorpion amongst the Crab!
It might be a bit lonely for her otherwise.