I know that from my posts that I'm the last one that should be talking about things from FFXI for FFXIV. However, that being said there is one big thing missing from The Black Shroud that was in zones in FFXI. It's a minor thing, but wind in the trees and hearing the leaves would make the zone a lot more inviting I think. Not only that, but having the bird sound effects almost utterly removed when a thunderstorm or rain storm moves through the forest. If realism is what you're moving towards, then for this area this is what I'd recommend.
Ul'Dah's area is pretty barren and what they have there with the sandstorms is pretty well done (having been stuck in one before lol).
As far as Limsa's areas go, more effects with the shrubberies and grass moving effects would be a very nice addition. Again, in FFXI in the Saruta and Ronf areas, even though the grass and shrubs were pixilated at best, still moved about. I know these are cosmetic at best and don't contribute to the structure of battle or story in the game, but still it would be nice to see the plants be more than just static and unmoving.