Since the systemd-change the vgaswitcheroo-methods do not work. Solution for me was: 
Just created aur package for systemd because the lack of support of the current package. The package is located at:  Needs testing of course although working for me.
Alternatively, the commands previously placed in rc.local,
- modprobe radeon
- echo OFF > /sys/kernel/debug/vgaswitcheroo/switch
can be moved to /etc/profile.d/yourscript.sh