After some work I came up with this:

If nobody sees anything wrong with it then I think I'm done.
Hello past me.
First of all, there's been a marked improvement from the first post to what you came to. It's just... not really doing it for me.
First off, the wooden planks feel sort of pillow shaded in a way. It keeps getting brighter as it gets closer to the center, and it bugs me. It'd look a lot better with a bit more thought put into the shading.
The silhouette of the chest is also strange. The top section curves in some weird ways, and the bottom part lacks any points of interest whatsoever. Aside from the lock, I guess.
Speaking of the metal on the chest, it looks a lot more like plastic than metal. Sorry, but it's the truth. There's no contrast in the colors, you've been careful to make everything a neat gradient. While that does have a certain charm to it, it doesn't work most of the time for making good pixel art. It just doesn't look like metal.
On top of all of this, you're using a disgusting amount of colors for the small image you have here. 21, not counting the background? Wow, man. You should need a maximum of maybe 12 for an image of this size.
Overall, I'm disgusted and horrified by you, me.
In all seriousness, I saw this being used on a site as my avatar and I decided to make it not look quite as bad. It was a nice experience visiting some of my old work and improving it. It was even more interesting to come back to this thread and see how much worse it was, haha.
Anyway, I thought I'd post the update here for kicks.

