So I will be working in a Fractal Design Define R4 case pretty soon, and will be expecting the best airflow and cable management as possible. One thing I would like to do is remove all 8 of the drive cages and move the 2 stock fans to the front. Aftermarket fans are in other mounts for decoration purposes. Even though there are no drive cages there are still many unique ways to install drives. I would like to use a 3.5'' to 5.2'' drive bay adapter and put the HDD under the optical drive, and the SSD behind the motherboard. Is this a good idea? And is it safe?
P.S. I will be using Corsair H100i liquid, will the brackets get in the way?
Since you are using a water cooler, it would have to be yes. The ssd will interfere with the bracket. It probably won't do much because it is screwed on, but there might not be enough room for it anyway.
EDIT: Find a bracket that will let you use a 3.5 and a 2.5 hard drive in a 5.25 bracket, I've seen them around.