Hahaha, I saw this and thought it was such a cool idea and went to look at 67Chrome's version. As I was looking through it, I was very impressed and a little surprised that I hadn't seen it before. To my surprise, it turns out I moderated them. Anyways, this is great. A few of the tiles seem a little flat though. Particularly the orange/red one in the middle of the bottom row and the purple shtuff in the second row. The orange light tubes in the middle of the third row could use a bit of a highlight on one side of the edge to show a bit of a separation between the surrounding blackness, as long as the image's resolution permits this. Perhaps you could rough up the black area with a bit of a metal texture as well to make it more interesting. And the tile in the absolute bottom left. I suppose that's supposed to be a glass window looking out into space? If the game's tiles permit you to use transparency (I'm not optimistic that this is the case), you could make the glass see-through and let people place their own space model below.
@ Hawkwing, I'll try the alpha thing on the starry window though, like you, I'm not optimistic. The orange/red one stays as it is, it's supposed to be carpet and I think it manages to look like it. I tried making the purple stuff a little less flat but I didn't like how it looked, may try it again if I feel like it. I'll try your suggestion on the orange light tubes tile. Thanks for the suggestions.