I really like this form factor.
I used to have a Thermaltake Core G3 which was unusual, but I really liked it (Especially modding it to take a 360mm radiator in the front).
The only issue I had was the build quality which was very flimsy.
Question for you.
What would happen if you moved the PSU above the motherboard in a horizontal mount and opened up the front with 3x120mm support?
Would this result in a larger or smaller overall volume? As it would be taller but more slender.
This would allow for 2x120mm radiator support and 360mm radiator support for full custom loops, although drive support would be significantly reduced.