1 word, "AMAZING" your GPU is awesome and should last for quite a bit of time. I have a lower end GPU 970 and an having a blast with Watch Dog 2 and BF1 on Med Settings.
Overall my wet dream of a gaming PC, thanks for sharing!
I contemplated a 1080, but I want more of a jump to be honest as I am looking to go up to 27inch 1440p monitor at the same time.
I am waiting to see if AMD step up to the plate with Vega, i really hope they do as competition is a good thing and NVIDIA have had the enthusiast market sown up for too long now. Otherwise there are still rumours of a 1080Ti, so I will see if that makes an appearance. Failing that I can wait.
Still waiting on Vega to rock up .... Hopefully the end of this month, then give it a month or two for the reviews etc and then there should be enough info to make a decision.