The 5800X3D is supposed to get really good scores on MSFS, but there’s not much in it between AMD and intel. I think some of the new 40 series gpus will be available around September. I think you should look to PCIE 4.0 for the M.2 making sure the Motherboard supports it. Built in WIFI 6 is always a bonus too.
MSFS uses almost 10GB of gpu Ram around NYC in 4K (2D).