This simple script obnoxiously warns max level players with a text overlay when they are missing equipment or have low iLvl equipment, common mistakes if you use fishing poles or hunt for BoE transmogs. Does nothing for players under max level, due to gear at said levels being chaotic.
Updates every 1 second. The threshold is having any piece of equipment (ignoring shirt/tabard obviously) below 70% of your highest item level, which so far works for BfA. (as of 8.1.5)
(alternate title: Gear Check)