I feel like I should put the darker shade below, because there is a shadow below, however I should remove it above the line, because there is no real reason for it to be darker here.

I will try it, thank you for your feedback.

I mean darkest shades right at outline example down left corner on 2nd face. It makes line messier.

But dont worry about being a begginer! Im sure soon you'll improve, I really like your backgrounds. 

Hello,

I am a noob at pixel-art, I don't know about any techniques and so. What does aa mean ? I know of aa in the video-game world, but not in pixel-art.

I like the 2nd (wizard?) best, he seems chill.

Could use a lil bit more work on the outlines, maybe less aa on faces?