I would like to suggest more of an environment impact in other areas besides the desert. There was alot of love put into the starting area and the desert that is sorely missing in other areas too.
I would like to suggest a snowstorm for the north. It would leave behind snow on the ground that you can wade through and that will slow down your movements and leave paths in it when you walk through it. Like in real life. this would add to the atmosphere alot and make it more rougher and tougher. Right now with the armor you can easily beat the cold but just turning up the cold in the north would make this meaningless. You have to feel that threat of the world that you are in more.
For the swamp some sort of coming miasma that rises up from the swamp and will give you a sick tag and drain away your health and stamina more over time. You would need to find a higher ground.
Near the pirate cost you see alot of stranded ships wrecks. This would be perfect setting for from time to time incoming tsunamis that sweep through the area and crash agaisnt the costs. Or if this is too much a heavy riandy thunderstorm where you see nothing with huge sways of fog to add to this.
I cannot think of anything regarding the tundra but in general I would suggest to put you vs the environment more into the foreground. It is a wild and rough land and it should show more. Because right now with the epics you pretty much got it all covered and can just outrun and outgun everything.