Some time ago Ozi Traveller helped me out for my logout problem sending
me 2 desktop environment independent logout tools (cb-exit and
oblogout, which essentially do the same, only oblogout is a bit more
eye candy). I had some problems with them but solved by changing the
localauthority settings of polkit.

Now, i have the chance to access my manjaro-openrc machine and i see
they do use oblogout in a slightly different manner: For them, oblogout
works as a kind of skin over a script called "fluxboxexit" (which
adresses both, systemd and openrc. For those interested, you can look
at it here: http://hastebin.com/ufeluvobiw.rb). The /etc/oblogout.conf
then look like this:

---
[settings]
usehal = false

[looks]
opacity = 40
bgcolor = black
# buttontheme =
buttontheme = foom
buttons = lock, logout, switch, suspend, hibernate, restart, shutdown,
cancel

[shortcuts]
lock = K
logout = L
switch = W
suspend = U
hibernate = H
restart = R
shutdown = S
cancel = Escape

[commands]
lock = ob_blurlock
logout = fluxboxexit logout
switch = dm-tool switch-to-greeter
suspend = fluxboxexit suspend
hibernate = fluxboxexit hibernate
restart = fluxboxexit reboot
shutdown = fluxboxexit shutdown
---

May be it's not that bad as an idea?