These questions have probably been answered many times since 1E, so apologies for my ignorance here, but here they are:
1 - A samurai is, by definition, a warrior sworn to the service of a land-holding lord, who pays them in rice taxed from the production of his land. The Hiruma have no land of their own. Who pays their salaries, and how? And if the Hiruma daimyo has no lands of his own, in what sense is he even a daimyo?
2 - The Kuni lands are described as "spiritually barren". How the heck do new Kuni shugenja train, or even know that they are in fact shugenja, when there's no spirits for them to talk to? (Since their lands are also described as ecologically barren, the same issue as the Hiruma applies- where does their wealth come from, and how do they support themselves?)
If this all comes down to them being subsidized by the Hida and/or Yasuki, then realistically, there is no Kuni or Hiruma daimyo. They're simply vassal families, by definition. I realize L5R lore plays fast and loose with the historical bases for the samurai feudal order as well as common sense, but if anyone has any marginally sensible rationalizations for these issues, I'd love to hear them. For my own games I'd probably simply say that following the loss of Hiruma lands to the Maw and the spiritual sterilization of the Kuni lands, they were granted territory from the Yasuki and/or Hida holdings in compensation, but alternatives are welcome.