I think you need to make it bolder and reinforce the nose and eyes to make them look more sculpted, like this:
the original blocks had a dark chiselled bold look, while the new iteration has a more soft and not very defined appearance and lacks depth not much contrast, and it looks like the features are more painted on in favour of 3 dimensional form, you should try to keep similar shades of colour to a minimum overall it makes the detail flatter and duller, and whoa wait just reread those are ears? thought they were some form of statuesque bevelling
maybe just forget ears and keep the idea of ornate detail instead
also you might like to do some quick studies of commercial video games and quickly dissect their colour combinations to see how they approach unifying the colours, the tree on its own doesn't look bad but when it is in game the way it tiles has massive gaps and reinforce a series of squares.
your desert setting doesn't look too bad, but I think you should try and unify the style between themes, the desert scene has more simplicity than the jungle, which is arguably more appealing,
also I tend to agree that the character doesn't match stylistically you should re do him/it with a more neutral form of shading if the environment isn't consistently lit from one side try to avoid light sourcing on the sprites it separates them even more. nevermind just read your reply, but it is something to keep in mind light source wise when you do make one.
also what someone said in your other thread this stuff is a bit high resolution, I think halving the resolution might be worth experimenting with, also there is a bit more of implying detail than actually having to render it, which might be easier at the same time. anyway keep pushing forward
