It really comes down to the TOTAL BUDGET and games played. I still have a GTX680 and play most games at 1080p, some at 1440p and for most I am at full quality or near full quality.
CIV5 is at 2560x1440, max settings, 60FPS.
Tomb Raider is at 1920x1080, almost max settings, 60FPS.
Crysis 3 is not quite maxed at 60FPS, 1080p but looks nearly as good as max. I would probably spend any extra processing on anti-aliasing if I had the GTX970.
Newer games are getting more demanding, but if tweaked properly I am still quite happy.
*I am not saying do not get a GTX970. If you have the budget go for it. I am saying:
1) You can have a great experience just below a GTX970.
2) You must properly TWEAK your settings (resolution, Adaptive VSYNC vs VSYNC ON or OFF, shadows etc) for the best experience, and
3) You must BALANCE the CPU, GPU and other parts for the best experience within your budget. Games vary on CPU load but on average any modern quad-core i5-4xxx is pretty darn good. If you can afford an i5-4690K and a GTX970 etc that is fine but if you have to choose a LESSER GPU due to spending extra on the CPU that may not be a good idea.
Thus, get the i5-4460 instead if it means you can get a better graphics card.