The top green on the tree gives it priority and should remain saturated or even moreso. Similarily for the top orange on the house. These two colors make that element not be part of a background. Almost all the other colors in their respective ramps could be playfully tinted if you so desire without any lack of clarity or priority, so unless there's a great reason not to, why not?
The rock face I brightened up I did so it would look like an obstacle, which needs more priority than a background element you would merely walk over. I tinted its shadows towards green to merge it a bit with the green floor tile.
The dirt shore color in your version seemed too bright, almost metallic or as if it's something edible so I moved the luma down a little and made it vaguely more warm.
The water - buffer - dark reflection was almost a straight ramp which gave ti me the impression that this is a manufactured toy world, so I made the darker color tint in the direction of the rocks themselves.
On the tree trunk I introduced green tints to complement the foliage and left the pleasing blue secondary ambient lightsource in-tact.
The biggest change is dampening the green field color a bit, a choice on which I'm a bit ambivalent but it would probably work out in terms of priority. A cost/benefit for losing that vibrant green, not sure if it's the best choice.
I changed the color of the cast shadow of the sprite because before it was the darkest and most saturated color in the mockup, not sure if you want a shadow to be the secondary focal point of the mockup after the saturated green foliage.
My overall impression is that your coloring method is a bit primary; not a bad thing in itself but it makes things look a bit plastic, the wonder of the natural world is how the whole is very complementary, mixed and complex.
