I won't change the hooking system anymore, it's fairly compatible right now with the most important overlay software and tools and any change could mess it up completly. So unfortunately this issue will remain unsolved.
Unfortunately, the Origin overlay can't be turned off for for some new games like Garden Warfare 2. It is always active and when combined with ReShade (also 2.0), it can sometimes cause frametime spikes aka mini-freezes.
I wonder if it could be worked around by an external injector that injects ReShade some seconds after the overlay?
Something similar has been implemented for Afterburner RTSS and it worked in this case.