Thanks again for your input Mr. @Chris Downs. I think I'd be fine with using NTFS vs ReFs as long as there was some way of preventing bit flip / bit rot / corrupted files.
While waiting for something in here, I have went ahead and installed Win2019 and fooling around with storage pools. It's a REAL PAIN to use. I tried to add two 10tb and 3tb drives (9.09 & 1.81 effective) using 2-way-mirror and it only gave me a storage pool of 5.37 max. I obviously wanted around 11.8 tb effective, half of the space. I even tried to do 2x10tb & 2x3tb, but nope, gave me 4tb effective.