I really liked the mod so if ideas worth anything to you I would like to provide some under here.

-Some titles must have requirements to create. Such as Grubashi and Amani Empires. Maybe they should only be formable via a desicion only Trolls can take, like the Empire of Zul. Other examples of it are Ahn'Qiraj, Zul'farrak. If it was like that for example when elves or humans conquered Amani or Grubashi, they would not form these dejure empires and they would disappear in time and be drifted to the conquerors de jure, which feels more accurate. Same for k_vermillion which should be only formable by dragons.

-Some provinces need an increase in their number of slots. Dazar'Alor, Utgarde, Blackrock, Grimbatol, Orgrimmar, Zul'Farrak, Eldre'Thalas, Ramkahen and ofc Ahn'Qiraj need atleast 1 more slots added considering the current number of slots they have. I think the only provinces deserving 7 slots are Stormwind, Lordaeron, Silvermoon, Dalaran, Boralus, Orgrimmar, Dazar'Alor, Ahn'Qiraj and if you ever add it, Ulduar. Other great provinces can have 5-6 slots which would be maxed should the player builds a wonder in them. This way the character owning these provinces can be powerful as in lore.

-For Ahn'Qiraj and Icecrown, instead of maxing their slots, reducing it to 1 but adding more special buildings and (for ICC) a great work can be an option. ICC needs a defence and perhaps an event similar to Ahn'Qiraj and "C'thun is Dead" event.

-Drakkari Empire's capital is not Gundrak at the moment, it must be so. Should you add Ulduar province, e_stormpeaks' capital must be there too. Otherwise during a gavelkind succesion owner of these titles will loose them. Drakari emperor will end up in the eastern kingdoms.

-The name of the great work Aztec Pyramid must be changed.

-Dark Iron ruler uses the title of Emperor. Dejure Emperor of Dark Iron culture must be called so.

-Shath'yar could use original eastern model of star for flags instead of christian style of shield.

-Exodar and Exodus Horde in Durotar almost never survives for long. Because Exodar have Satyrs near and legion takes care of them soon. And Horde in Durotar is too weak to survive there. An Ironforge-Gnomeregan like Exodar-Kaldorei alliance event may prove useful though I don't know how it works for the AI. And Exodus Horde could spawn in both Durotar and Northern Barrens.

-You have many lovely landmarks. The Sunfury Spire, Dazar'alor Teldrassil and Nordrassil would be great additions. Kalimdor don't have any.

-Zandalar could have a form alliance/horde like decision to make loa trolls join him, which happened twice in wow during cata and pandaria.

-I think Magni, Ymiron, Rastakhan and the Dragon Aspects deserve character portraits.

-Characters like the Old Gods, Azshara and Sargeras could be added as religion-tied off-map rulers. Granting boons and all like in Elder Kings mod.

-Karazhan and Ahn'Qiraj should be pockets like Twilight Grove.

-If the date started at the year 10000+ since the sundering, you could've added many historical characters such as Dath'Remar and Rastakhan's ancestors.

Well easy to say than doing i guess. Wish you luck.