We have:
Crystalline:
- Old Sharlayan
- Coerthas/Alabanthias Spine. It's not quite clear, but its very Heavensward like.
- La Noscea
- Hingashi
Frontlines:
- Carteneu Flats
- Seal Rock
- The Azim Steppe
- Coerthas (East Shroud that is no longer available as of 2.X)
Rival Wings:
- Thanalan
- The Hinterlands (Used to be Sharlayan)
The Feast (RIP)
- Crystal Tower Training Grounds
- Lichenweed (West Shroud that is no longer available as of 2.x)
- The Wolves Den (Limsa)
My point is that the only remaining populated (Visitable) areas not covered in PVP are
Thavnair, Eulmore, Crystarium, Garlemald, and Doma. Here's my case for all of them.
- Thavnair makes the most sense because it has been in the story since 2.X at least, and we have a thriving city there. After the the end of Endwalker it makes sense that they would want to boost attraction to the city, so why not a PVP map? Plus it would provide flavor from the East, and Ilsabard that is very different from Kugane. I think its the best option. Plus if they tied alchemy, dancer, and India inspired gimmicks to the map I think it would be a spectacle.
- Garlemald makes zero sense. As much as I want to see a creative magitek stage, I just don't think its ready. We'd be more likely to get that out of Bozja, which as of right now is not a very stable place. It's pretty much gone. Maybe Castrum Lacus Litore will be basis for the rebuilding of a city one day. A Garlean stage will have to be after a restoration effort, and probably a couple years down the line.
- Ala Mhigo is a city state that is so underrated it hurts. Honestly seeing anything with it would be great. An Ala Mhigan pvp map would give it some more deserving love for an abandoned inaccessible place that is supposed to be important lol.
- Crystarium would be beautiful, but might be too similar to the Sharlayan stage. However, I wouldn't have a problem with it. Its unique visually, and goes with the Crystal Tower theme that is popular quite well. The problem is explaining how people on the source would know about it to make it a pvp map. I STILL think with the theme of a crystal mechanic that it would be a great idea for a map down the road though.
- Eulmore, while vastly different, and would be quite exciting, having maps from the shards provides a problem. First shard travel needs to be more well known in the lore.
- Bozja while it would be amazing to see the technology used, it would have to be an imagined ruin of some kind. Maybe based on the raids, or around the castrum. I just don't think its ready. Needs an already in story reason to go back there first before we get such a map.
- Doma would actually work, and could easily be a pvp map. I hope it gets its chance to shine someday through PvP. Yanxia is a beautiful place with its own spin on things in the East, even if they are comparable to Hingashi.
- Ruby Sea could exist as a map underwater and that would be cool. Maybe the Raen could finally let the world have some communication. If not them, it would likely be Kojin based, and that would be awesome.
Any other city on the map that we haven't actually gone to makes no sense, and shouldn't be suggested until MSQ brings us there first. As much as I'd love Dalmasca, Valnain, Bukyo, Corvos, Werlyt, Naxia, etc. It isn't gonna happen.