Political stability: Hazo is not good at politics.
This is 100% wrong and only depends on what we feed Hazou as information.
Hazou had little problem convincing Neji, Ruri and Minami to join the Trade network.
He probably lost the Minami roll, if there was a hidden one and we still got overall what we wanted.
Hazou actually won his roll with Mari's help against Yasuji and we got our Koi fish. (By selling MEW and Earth clones + Oro's biosealing thing, lol what a failure Yasuji)
And Kei got her wins against Yoshida and Arikada.
In an example where Hazou was alone with a Kurosawa to make a deal the most likely outcomes where we lose is, we either don't get anything or we have to pay more Goketsu stuff for Kurosawa stuff then when we would win the social rolls. Not exactly the end of the world.
Because we really aren't getting randomly assinssinated in the middle of Mist, with a summoning scroll, during an offical visit. Unless the Kurosawa want an investigation by a goverment that just kicked them out. But then they are simple idiots. (Plus we can bring "Bodyguards" anyway)
As for the rest of this point:
- You want to become the sole communication Clan? Are you really sure you understand what you're asking here? The Nara aren't in charge of the whole economiy/military, they are simply important because [SmartBrainMagic]. And we were never told why the Hagoromo have so much influence over marriage (which they don't have anymore anyway), but I doubt that Asuma wants to give that much power to a single clan, again. Leafs "Intelligence Department" for example was also run by Ibiki Morino (clanless), who is appearently dead, so it's probably Anko, so it's Ami again.
And to actually develop and propose something new:
Maybe we can talk with Mari about the Takahashi clan and their ninjutsu stuff? They might have or can make something for "Mental resistance".
Mari isn't banned from Isan, can lie to most of them, understands what we actually want and can be discreet about it, can return with the Yoshida to talk with Kagome/Hazou and if that actually works we can pull in Ino (or do that before if Mari likes the idea).
Us selling some Asuma approved seals (including Skywalkers, unless he really only wants weak allies) and other stuff should be enough to get an centuries old highly ninjutsu focused clan to help with an "secret" non-combat project.
I mean we can try in Leaf, but who is the best ninjutsu maker after Oro? How confident are we they are better/worse than them? And whats really more dangerous? Working with a clan who possible "knows" about SC or working with some people who know only the most general things,
at best?
edit: Takahashi also met Orochimaru, working with him on anti-mind-blast stuff, shouldn't be a crazy idea for him.