I think you should remove the hard-coded 120 fps cap in the editor. I think this cap makes it much harder to optimize your graphics settings, especially with Oculus Rift coming where you need a much higher base fps. Mobile games also require you to aim for a much higher fps, considering the game will be running on low-end devices.
I know you can use the Standalone Game preview mode, but this loads much slower and you cannot adjust settings on the fly, so it’s not really a viable alternative.
The cap is also confusing and made me waste a couple of hours trying to find the right settings.
There are many other alternatives to cap fps, including r.VSync, t.MaxFPS and Smooth Frame Rate, so I don’t think removing this should be a problem.