What did the Babylonians speak?
No language in particular; they just Babeled.
All we have right now in the screenshots are spruce trees; I'd very much like to see a regular oak-type forest, or snow-covered pines as alternative terrain features. Functionally identical to the current forests, of course, but more suited to warmer or colder locations.
also maybe denser forests would be nice
I like the Carthaginian thing in principle, but it was too easy to inadvertently damage or kill your units if you assign a movement that takes multiple turns. Maybe a less severe penalty and a cap on damage (only reduce to 50 HP minimum) would work.
I've played with some mods that make certain tiles (like jungle) impassable until a certain tech, like ocean tiles. That could work with desert, too. You don't even need a different tile type for "inner desert" – you can just say that you can only move on desert tiles adjacent to another tile type.