Also if you're wondering that case will fit a Hyper Evo 212 or similar heatsink. I have the same case and heatsink but there is no room above the heatsink, it's almost touching the side of the case.
you really don't need aftermarket heatsink/fan
stock is fine if you aren't overclocking
I thought out of the GTX 9x0 series that only the 980 could run max
980 sucks because you could just get a 970 (runs max/ultra-ish at 1080p, ~30-60 fps depending on your game). 980 is like "lol what am i doing"
get a 970 or a 980 ti, not a 980. horrible p/p ratio.
from what i can tell, that system is p good. if you want pro help, go to /r/buildapc and go to their irc channel.