When we started this project we were informed that the project needed to be seen as success by everybody. We can't really afford to ignore both Plumes AND MoI at the same time and expect being rewarded for it. CRX can't afford making anybody feel slighted, not when she is planning to conflict with her mother in the future.
The definition of success is fluid for each group, though. Our definition, the one that is going to make all our risks worth it, is establishment of a foundation for long term diplomacy, trade, and cultural exchange. An addendum to that is hammering into the skulls of every group that we are negotiating with another policy and nation, not just "Barbarians". We probably need to reach an even higher level of acceptance than the Xuan have, because the Emerald Seas aren't as isolated as the Savage Seas.
All the Plumes care about is using these negotiations to keep the Twelve Stars and Ith-ia from gathering more allies. As long as we can get some assurances the White Sky will help steer other Cloud Tribes away from the fight and not join in, the Plumes will be "happy" with the summit. They're a low bar.
The other Provinces don't matter much, directly. Except for the West, where we need to convince the Suns to stop poking at Freya. We also need to try getting the West to agree not to raid, invade, or harass the Tangled Pines and western White Sky.
Our biggest opponent is going to be the Ministry of Integrity, which would much prefer that we lable everyone south of the Wall as barbarians and move on. They have no investment in diplomacy or trade. They don't have any "success" condition here at all. We literally need just to keep them from actively sabotaging the event.
Keeping favor from the Emerald Seas Nobility high is the biggest priority. Without support at home, we have nothing to offer. White Sky next, because we need someone to talk to. The White Plumes is third, but a distant third. They just need an assurance we won't screw up their on-going campaigns. And we'd like them to, ya know, not start a war.
Favor from the ministry is dead last priority.