In the Properties Toolbar, the list of Layers has a light bulb for showing whether a layer is On or Off.
I find the difference between On and Off a bit difficult to discern when scrolling through the list, especially at speed.
It's probably a Graphic Design or Accessability thing, but if the Yellow was a much stronger Yellow, the contract between On and Off would be greater.
I'm not sure if the yellow light bulb can be any "yellower", but perhaps an idea it to have the "Off" layer colour grey or blue (instead of white) to differentiate better.