Grand Cathay End Goals?

Goal setting and roleplay is a way to fight the potential monotony of later campaigns. So I set loreful goals: once the Empire is reestablished I will crusade in Araby and make colonies in Lustria. I remake the lost elf or dwarf empire as their respective races, purge the lands of chaos and 'redistribute' the younger races as lizardmen. Landmark mods REALLY help with this, adding landmarks across the map for me to reach.

I am somewhat stumped by Grand Cathay though. Reuniting Grand Cathay is no small feat, but once it's all conquered or confederated (the halfway point in my other Order campaigns) I don't quite know what to do, Any ideas would be greatly appreciated !