I don't like this small case to fit ATX motherboard because it can't cool it if it's overclocked.
Why not making it fit for mATX or ITX boards (including OC versions ... look Asus ROC solutions).
Today every vendor offers high performance mATX MBs that offer 2x VGA over Crossfire/SLI.
Here is my solutions made with Microsoft Paint on shown pictures inhere.
Idea, make space to fit two 240mm radiators, on top and back, make drilled/mashed bottom right below GPU space on bottom and put dust filter (lets call it VGA filter!) giving 2nd air colled GPU enough enviroment temp to pull in for its fans.
Put PSU on TOP, and one 5,25" drive for ODD with 2cm space distance of PSU intake fan on it's bottom. Then it follows by 3x 3,5" drive mounts or 4x 2,5" drive fixed mounts and 120mm intake fan as shown on pic.
This leaves enough space to put any size of GPU builder would like because it won't have anything to block it's installation or cable management.
I don't belive that resizing case to any smaller format would drastlicly lower cost of material and it's late sale price on market. Also this huge "empty" space could help pro water cooler solution builders to put pump and tank.
I don't know anyone tried put power supply on top, it could help take out extra heat with it's own exhaust fan and it does looks like mirrored standard mounting on top, while sacrificing 2x5,25" drive space but gaining extra 120mm fan mounting place or second 240mm radiator mounting place. and keeping case size as mid tower (how many mid towers have top and back 240mm radiator mounting place?)
Here r my fast created Paint edited pictures of it's back and side:
https://drive.google.com/folderview?id=0BzQqtiL05Ao8M1lzaERkN2JsVUE&usp=sharing
I don't have CAD to put real measurements,