+/- requires root

[CamilleScholtz]

is there anything I can do about this?

[bricewge]

This can be achieved with udev rules, as explained in the ArchWiki:

ACTION=="add", SUBSYSTEM=="backlight", KERNEL=="acpi_video0", RUN+="/bin/chgrp video /sys/class/backlight/%k/brightness"
ACTION=="add", SUBSYSTEM=="backlight", KERNEL=="acpi_video0", RUN+="/bin/chmod g+w /sys/class/backlight/%k/brightness"

Don't forget to add yourself to the video group.