I upgraded to FF and the 5D3, last year, after considering it since the first 5D came out, 8 years ago. The bokeh was what tempted me the most, but I never felt I could afford it and did stop by the 7D before I went to the 5D3. However. Since I started looking at FF, I never again bought an EF-S lens. All my new lenses where EF lenses that would fit a future FF camera
Maybe that is a way to go?: Get better glass now, and then go for the 6D2 in a few years, when the quality of the sensor will make a bigger difference and you want to change your body anyway.
By the way, I want to mention that the 5D3 totally outperforms the 7D (which I believe have the same sensor as the 7D) in terms of low light performance. I have about 3 or 4 extra stops of ISO to get the same quality shots, so if low light is an issue for you, FF makes much more sense.