Turn you screen fully bright. Open Terminal, type nvram backlight-level. Note the value. Create a logout hook to run nvram backlight-level=<value>. In my case the value was backlight-level %a0%06.

Turn you screen fully bright. Open Terminal, type nvram backlight-level. Note the value. Create a logout hook to run nvram backlight-level=<value>. In my case the value was %a0%06.

If you run it interactively, you need to use sudo:

sudo nvram backlight-level='%a0%06'