I was thinking of making a custom case very similar to the corsair one. Two radiators, intake fans on top and bottom.
Layout: https://assets.pcmag.com/media/images/536421-corsair-one-pro.png?thumb=y&width=980&height=417
- Case needs to be pretty airtight
- Intake 140mm on both top and bottom
- Sff psu above the motherboard, Gpu with powered riser on the other side of the case.
- 2x flexible 240mm aio without any fans. E.g. http://www.fractal-design.com/home/product/water-cooling/s24
- Positive over negative pressure (like the corsair one) to keep the internals cooler
- Extra room on bottom for radiator tubing. Kraken g12 on gpu, fan as exhaust
- All internal components mounted to center panel, mounted to a frame.
Layout: https://assets.pcmag.com/media/images/536421-corsair-one-pro.png?thumb=y&width=980&height=417