A few ideas that you might try:
1. the Icevale
Make the crags/spikes/whatever more spiky. More linear, sharper. That would look more like ice, in my view. The dunes/snowdrifts... I don't know. Less of them, I would say, and perhaps more in the style of a flat crested wave... windswept looking.
2. dead lands
Again, I would reduce the amount of bushes, and spread out the texture overall. Perhaps spread it out at the borders even more, so that it fades into the surrounding areas a little.
The volcanoes are absolutely amazing, though!
3. the cliffs
Two things I would try here. First, get rid of the shading and add some shorter vertical lines of various length, so that they don't reach the top. Second, add a little vertical variation to the top line, so that it shows some "v" cuts.

A lot of work for sure, but it was worth it, wasn't it? It is a stunningly wonderful map!