I like how the name "Elemental" sounds, but frankly, there isn't that much of a focus on the various elements (Fire, Air, etc.) except for a bit on the shard/magic side of things. For a game with elements in the title, they should play a much more prominent role. I've never seen this as a major component of the game, though, so I'd ditch that descriptor.
Similarly, do we really need Ceresa to be the focus by keeping the terms "Fallen Enchantress"? It seems too specific about the plot-line, and in many sand box games you don't interact with her at all.
I'm very supportive of a new branding completely. How about using the main continent name- Anthys?
One option would be Anthys Civilizations. Since this game is going to be somewhat similar to Galactic Civilizations, it would keep the parallel between these since they're similar but set in different genres. The only thing I don't like is the difficulty of spelling/pronouncing.
I'd love to see something like-
[Next game] Civilizations
This is all assuming you want to keep city building/management at the core of the game. If they are TBS games with civilization components, this makes sense.