looks nice, two suggestions:
1) KISS. Make the front and rear identical, similar to this image. might not rack as nicely without bottom/top/sides, but allows clean 3-wide builds
2) Re-design it so that 3*120mm fans cool 8-10 blades packed more densely. This would be terrific for those underclocking to 150GH/210W.
Here's the implementation of the above for the S3.
Also can be for S1.
https://bitcointalk.org/index.php?topic=681059