Yeah, seems like it (it was probably going to be the place for the wedding). I guess it's just that they didn't really show that much of the religious side (beyond what we, as Noctis, experience with the gods themselves), like in, I don't know, X.
Well, I'd say that personal faith is a much bigger motivation for a lot of side characters than it is in most FFs -- Camelia, for instance, is willing to sacrifice her city's infrastructure to the will of the gods, even if she insists on the safety of her people. It shows up in the way a lot of characters (particularly those directly connected to the King and the Oracle) talk, too.
The biggest difference between the portrayal of religion in Eos vs. the portrayal of religion in Spira, I think, is that the organizational hierarchy of the world's primary religion was important to FFX in a way that it wasn't in FFXV. Maesters, High Summoners, and Summoners were all important to Tidus and Yuna's stories, so we needed to know how they worked. On the other hand, we don't really need to know much about the way people in Eos worship when the Oracle isn't around, because that doesn't really affect either Noct or Luna.
And indeed, Prompto's is the one with more potential imo, as his story is the one that might have suffered the biggest cut (we don't about Gladio's thing or how Ignis was blinded, but you'd think that Prompto's Niflheim heritage -especially if he's indeed Verstael's son- should be important and not just instantly forgotten). He already has good clothes, for once too!
Not gonna lie, seeing Cor with Gladio upped my interest in that one significantly. XD Pairing those two together makes me think that the story might have something to do with both of them trying to cope with their perceived failure to help Insomnia and their King in a time of need, which is a lot more compelling than "Gladio goes off alone to get revenge on... something."
Of course, that one image we got of Prompto is more compelling still. I love that outfit for him (maybe we can get winter clothes for the other three, too, as an ice-resistant equivalent to the Thermal Suit?), and he looks so conflicted. I wonder if he finds out Verstael is his father and then has to kill him... or if he can't bring himself to pull the trigger on Verstael as a human and ends up having to fight him in daemon form.
And honestly, didn't think about Luna appearing in Ignis' DLC. It's possible, indeed. Wonder what it'll be about (at first sight, there's not that much room to explore if it's indeed set in Altissia). A very interesting thing for these DLCs would be having the majority of them happen during the past and then a little bit in the future, to show how they dealt with the World of Ruin (I guess it could be easy to find some sort of thematic thread that would make the future part fit the past one).
I wasn't really thinking about Luna appearing in Ignis' DLC -- given her location during the fight, that seems unlikely. The devs have mentioned they know there's demand for Luna DLC, though, so there's no reason they couldn't do it post-Season Pass.
Ignis' DLC could easily include
Ravus, on the other hand, since he should have been in the area but we haven't been told what he was up to.
And yeah, Carnatica seems to be like you say (makes sense considering its landscape). Wonder how many towns were initially in the game. The Santorini one not being there hurts tbh, I love Balamb Garden (and that's closest to Santorini in the series).
I'm not inclined to think there were
that many towns that were partially developed but left out of the final game, particularly not apart from ones we've seen material from (i.e. pre-fall Insomnia, the Santorini-inspired town, a few outposts that are marked as outposts/bases in the train segments, and Tenebrae).
The weirdest thing about the Santorini-inspired town, though, is that it feels like it'd have to be part of Accordo, but there's no exploration of that area whatsoever outside of Altissia. It's easy to speculate that that region was intended to be explored by boat, but I'm pretty sure Tabata said early on that the boat was intended to be a one-time thing that you couldn't control, so...?