I'll preface this by saying that I have no evidence it will happen, and I'm not even speculating as to its likelihood —*it's just an idea that I believe would be widely welcomed, and is well-positioned to happen!
What if the next major residential region added to the game is connected to Tuliyollal? And beyond that, what if it is an exclusively instanced residential region?
I don't believe that FFXIV will ever switch all of the established housing districts (Mist, Goblet, Lavender Beds, Empyreum, Shirogane) away from the current ward/neighborhood format. That's never appeared feasible to me, and I've not read any particularly good arguments for how/why that would even take place, despite housing scarcity on crowded worlds.
But it feels as if significant strides have been made in the game's server capabilities, and I believe that Dawntrail (or perhaps the next expansion?) are positioned to offer something new and different for housing enthusiasts in-game. Adding Tuliyollal (or a different region — this is not an "I predict..." or "Called it!" type of post) as an exclusively instanced housing option would generate an immense amount of good will in the playerbase, and it feels like a prime opportunity to do so. It could help to thin out lottery frustrations, make more room in the existing wards, and give players more variety in what type of housing they want to pursue.
Island Sanctuaries felt like an exploration into whether this is possible, and the demand for more customization in that space tells me that the demand for actual, instanced housing is still quite high. And because I believe existing wards will continue as they are, the addition of whatever region is considered next for new residential content feels like a great opportunity to not just add a new aesthetic, but a new (highly demanded) experience!