I think that by making the transition from the top plane to the sides a little less sudden you'll add volume and make it more believable.
My rough and dirty edit:


I also think your palette can use some work; It's rather monochromatic right now and although that's a valid stylistic choice I personally think you can make it look better by modifying some of your hues.
Overall it's looking good so far, and I prefer the textured cracks version.

Looks great so far.
The foliage looks too contrasted and saturated compared to everything else, And I agree with Rargh about the transition to purple being too abrupt, I think it flattens it.
I also feel that the cliff side needs more contrast - it's currently using approximately the same range of values as in the ground surface, while it should probably have at least the same range as the tree trunks do . And as for the cliff shadow- it just needs to extend more to the right, to duplicate the 45-ish degrees angle used on the trees.
I love the natural grass borders, much better than the square ones In my opinion!

Looks great, much better without the black outline, IMO .
Is this going to be used in an actual game or is it just for practice ?

Cool, but personally I feel that the box on the left displaying the selected ship is a bit useless, it just repeats the same ship graphic which is already highlighted clearly enough. I think it should either show the ship from a different angle (closeup, perspective) or show some other relevant information.

I like where it's going, the new version is already quite an improvement over the previous one, in my opinion.
I think the main problem right now is that it's too noisy, which makes the forms a bit difficult to read. Try shading the larger forms first, and add details only after they are readable .
I did a quick paint-over (pixelover) to show my point:

You can see that I removed a lot of the texture but kept hints of it in some areas such as the beard and top of the cap, I think it's more readable this way.
And on a sidenote- I only used colors from your original palette, but managed to reduce the color count from 24 to 13 (and it can definitely be reduced further). It's not crucial if you're not actually developing work for a technically limited hardware , but I find that limiting my palette makes me think differently about the use of color and the ways colors interact in a pixel based piece, It's something worth paying attention to .