Great!

What software are you using? You need something that displays the palette and lets you change colours and see them update in the canvas. I normally start manually sorting colours in the palette by value and then comparing their HSV values. If their values are similar enough, I copy one of them into the other and merge them into a single index.

The purple hills are interesting. I think at least their value is a big improvement; they seal the bottom of the piece nicely and push the eye up to the subject. New greens are good!

I imagined the face basically being a stern brow, white eyes (lids pulled back, you kind of already have this), but an otherwise calm face. I think it'd be funny, almost satirical. Maybe a slightly pouting mouth, too.

Here's an edit on the hill:


It gives it a little more volume

Aaaahhhhh, ridges, so thats how he got onto the hill!

The places just under the ears almost look like cheek bones, or they could his neck. Can you clear that up? :/