Skylake only has 16 PCIE lanes available. Which means that with you two GPUs, you can't use ANY other PCIE devices. No PCIE SSDs, WIFI, Soundcards - none of it, or you'll cut one of your GPUs down to 4x from 8x.
So you may be one of the few cases that should go with a 2011-v3 board.
That RAM is slow. It may seem bling and nice and expensive but 15/17/17/35 @ 3000 is not very fast.
You can easily get 14@3200.
Again, you mention sound cards and wifi - you will not be able to use PCIE devices with this build - your GPUs take up all the lanes.