GTX 980 Ti Build

Hello, first time building a desktop!

Before anything, here is what I am going to be doing with this setup:
    
     1. oclHashcat (WPA and a few others)
     2. Some gaming (GTA5 and similar)
     3. 4k video editing/picture editing
     4. Average uses (YouTube, 4k video watching, etc)

Other notes:

     1. I have an absolute MAX budget of $3,000
          -Also need to buy a monitor and case
     2. I may wait for Pascal chips to arrive and purchase them instead if there are significant improvements
     3. Primary OS's will be Debian 8 and Windows 10
     4. I may buy some not critical components used from eBay/Amazon or similar

Part List:

      Motherboard: Gigabyte GA-Z170X-Gaming 7 ATX LGA1151 http://www.gigabyte.com/products/product...id=5481#ov
      Processor: Intel Core i7-6700K http://ark.intel.com/products/88195/Inte...o-4_20-GHz
      CPU Cooler: Cooler Master Hyper 212 EVO 82.9 CFM Sleve Bearing CPU Cooler http://www.coolermaster.com/cooling/cpu-...r-212-evo/
      GPU: 2x Nvidia GTX 980 Ti (Reference Design) http://www.geforce.com/hardware/desktop-...gtx-980-ti
      RAM: 32GB G.Skill Ripjaws V Series DDR4-2400 http://www.gskill.com/en/product/f4-2400c15q-32gvr
      SSD: 500GB Samsung 850 EVO 2.5" http://www.samsung.com/us/computer/memor...75E500B/AM
      HDD: 4TB Western Digital Black Series 3.5" 7200rpm http://www.wdc.com/en/products/products....d=760#Tab3
           -May drop to 2TB instead
      PSU: EVGA SuperNOVA 850 Gold 80+ http://www.evga.com/Products/Product.asp...G2-0850-XR
      Other components below

Semi-Complete Build: http://pcpartpicker.com/p/7WXHf7

Questions:

     1. Are there any alternative/better/cheaper parts you'd recommend?
     2. Can you recommend me a good case+cooling fans?
     3. Am I safe buying reference design cards for both hashcat and some gaming/video editing?

Thanks!