Nice write up! One thing I would have enjoyed seeing pictured is the back of the motherboards. I've never understood why some reviews don't bother with shots of the back of the reviewed boards. My x570 Master comes standard with a backplate on the back of the board, which not only lends it weight, but most importantly keeps the board from any sort of warp so that the dimensions are always the same (fits the stand-offs perfectly, etc.) Sometimes a pic of the board back can offer some insight into board construction.
All of these mboards disappoint. I'm not going to go Intel, so I'll only compare and look for AMD mboards. MSI/Asus--far too expensive. Just ridiculous, frankly. You're right, the best board buy seems to be the Asroc you've mentioned. The GB board features almost the identical sound hardware that is featured on my x570 Master! They couldn't have improved it? Sad. $360 for my x570 was a great buy, considering the features it offers. The x670e Aorus Master costs $140 more than my x570 Master, but lacks several of the must-have features that made the Master so popular are not present in the x670e Master--including, incredibly, no backplate Clear CMOS button! And last, these are all E-ATX, which is going to require a new case purchase, on top of the rest of it. The 5800X3D is looking better all the time.