IC: Eberron High Level
Yeah, there is a lot left out. For starters, which rule system -- 3.5, Pathfinder, 4E, or 5E? Gestalt implies one of the first two (as that option doesn't exist for the others).
While I'm not very fond of gestalt play, I'd be willing to give it a try if the story looks solid enough. While I always love me some Eberron, just putting it there isn't enough any more.