You aren't going to be pushing much over 60FPS in newer more demanding titles unless you reduce image quality settings. I'd get a 1080 or even the yet to be released 1080 Ti for 1440p/144Hz. The 1070 is a little faster than my 980 Ti and I average ~55FPS in The Witcher 3 with all settings maxed at 1440p. ~60FPS in Fallout 4, 58FPS in Rise of the Tomb Raider etc.