Hey,
So, I've been doing research, and found a out that the best value for money Graphics Card is the Nvidia Quadro 4000. I'm not sure wether to bite the bullet and buy it, or wait until later to buy an RX 560. The Mac Pro is the 3, 1, which can get Mojave when using Dosdude1's Patcher. Looking...
I am not an engineer, nor programmer but a possible scenario for Mac Pro GPU support in 10.14 could be a
PCI/Passthrough solution of MAC-EFI/GraphicsCard to second GPU/Metal/supportedDevice port output (without Mac Efi), maybe AMD Vega only which are officially supported in eGPU configurations...