Considering your (rather immense) budget, I would seriously consider going workstation grade with your motherboard / cpu / ram, although it is completely up to you. I would probably build something with a Xeon E5 1650v3 and ECC DDR4. With such a high budget, I would also include an NVMe SSD, such as the Intel 750 400GB. For the ability to upgrade to 3 or 4 way SLI in the future, I might consider a CPU supporting a full 40 PCIe lanes, such as the 5930k or the Xeon that I mentioned, since that is one of the major appeals of the X99 platform.
Your graphics solution is wildly overkill for single panel gaming at 1080p; I would allocate more money to a 3x1440p setup, as the price for this resolution has fallen considerably. A single 4k gaming monitor could also be fun, although not necessary.With 2x 980ti, you could probably game in surround on all three.