Thank you! It might sound like an excuse but in fact I thought, if I made the background a little more pale, the character and monster sprites would show more of a contrast against the background - but I guess that's not nessessary.. ^^ well, i know it for next time.
Aquamaryann looks really awesome! Unfortunately, the rest of the scene looks a bit washed out.
Main character is really funny but the rest of picture (may be instead of bugs) is on much lower level than the character. :(
Watermelons, big bugs... I like it! If it was a real game I would play it! 
Those jewels are kind of lame but the rest is all nice and colorful.
This is nice! I like the style, atmosphere and palette, but still may point a few things for you to improve: The contrast you had already pointed. you culd use different outlines or change the values, saturation, etc. same happens between that cupule thing and the cloud. Also the jewels needs more detail at front. otherwise they look flat like a cutted glass (unless that's the shape you were pretending to give them). Drawing a few dispersed leaves would help those trees as well, and finally those bugs at right are in a too weird position. ¿...?