Best GPU and WIFI Card

Hello Everyone,

I run a Hackintosh for transcoding footage on-set with DaVinci Resolve, this is my current setup:

Mobo: Gigabyte X299 AORUS Gaming 7 LGA2066 ATX
CPU: Intel i9 7960X 16 Core 2.8GHz
CPU Cooler: Corsair H100i V2
GPU: Gigabyte Aorus 1080Ti
RAM: 64GB Corsair Vengence
Storage: Samsung 960 EVO 1TB M.2 NVMe SSD
Storage: Samsung 960 EVO 4TB SATA SSD
Accessories: GC-ALPINE RIDGE TB3 Expansion Card
Accessories: OSX Wifi Card
Accessories: Blackmagic Decklink 4K
Power Supply: Corsair RM1000i

I haven't used my rig in a little while and am looking to refresh it. Currently I am running High Sierra due to NVidia Drivers as I have a 1080Ti Installed. I'm thinking the best bet is to sell my 1080Ti and my 980Ti (currently in storage) and fit out my system with an AMD GPU as I'd like to upgrade to Mojave or Catalina. What is the current, readily available, top of the line GPU? The New MacPro can be customised with a Radeon Pro Vega II w/ 32GB or a Radeon Pro W5700X w/ 16GB, any idea when these cards will become available standalone? Thus being able to purchase and fit them into a Hack?

While I'm at it, the OSX Wifi Card has never been crash hot. Whenever heavy downloads/uploads are in the works the touchpad input via bluetooth lags until the downloads are finished. Very strange. Is there a better option card wise that I can install to get native WIFI / Bluetooth / Airdrop?

Any help or advise you can offer would be appreciated!

Kind Regards

Brad