The other mamoojal at the bottom- which from the picture's composition makes it a logical deduction that he is the other royal rival claimant to the throne who hired Thancred and Urianger. Hazarding a guess, he's the natural-born child of Gulool Ja Ja and it'll be interesting to see if his attitude towards his adopted sister is amicable or deeply contentious - the writing is full of possibilities. The catboy in white might be from Sharlayan but I think is more likely to be a native of North Tural and some sort of faction leader or important there. Our key guy in Heritage Found I'd wager. Brown-haired girl has Ellone from Eshtar *cough* Mikoto from Terra *cough* knowing nothing else she's probably connected to Solution Nine.
Solution Nine. Yeah that's a shock. Not that there's a more advanced than the Garleans purple-themed society in North Tural who look posed to take over as fresh antagonists at least temporarily; I'm giddy to be right about that. The full-on cyberpunk aesthetic was a surprise. And speculation can go anywhere so I'm trying not to cling to any theory because that leads to disappointment. EW's patch content and the name from Zidane hints at a Shard-connection, but it's not guaranteed. The proto-language could be a Shard clue or it could be, along with that one suspiciously angled building, a hint that Nine's civilization rediscovered and innovated upon Ancient ruins and technology like the Bentos Ondo did. Or everything there is one-hundred-percent native to North Tural and it looks that advanced because they have an overabundance of lightning aether for electricity and ceruleum and they could progress their technology relatively uninterrupted by most Calamities because Hingashi showed back in SB that the Calamities weren't as intense and civilization resetting the further from Eorzea's epicenter you got. Could be the civilization before Tural's Federation formed or not. Could be a play on Eshter, Cocoon, Bevelle, Zanarkand.... If it is Terra, and the story involves Shard soul immigration, it could be Ardbert and Golbez's goal again. Or, maybe in a reversal, it's people in Tural that were trying to fling their souls onto another Shard.
That the next version of Ishgard Restoration isn't a repeat with Garlemald but more exciting and unexpected by involving the cosmos - did not see coming and makes me as someone that plays DoL/H more than combat jobs very hyped.