Being a pixel noob, I will stick with abstract advice and lean away from actual in depth pixel art techniques..
I think:
1. You should post any other background/sprite examples you may have so we can see how it coalesces and fits in. Imagine if in the beginning stages of Minecraft, a pixel artist sent in the pickaxe sprite for editing here, and some forumgoer made it all badass, but guess what, now it doesn't fit in with the style of the rest of the project.
2. You could tell us how much time you have for this project (college, cool) and how long it took you to make this so we can make an accurate judgement of how much work you may put into your project. 1,000 hours is a lot more time for shading and dithering than 50 hours. Also are you going for a decked out game along the lines of Final Fantasy, or following a concept as simple as Frogger? That weighs in big time.
I like it. You obviously worked at it to make it a smooth walk transition.