In respective situations did you notice the display switched to 'off' and back to 'on'? It shows the actual status now and does no longer bridge 'off'-time.

I gave it a try and think a coloured indicator is a good idea. In view of the fact that the button's text colour depends on your current theme - and I also like the additional symbol - I just added an option to choose between indicator styles (symbol, blue, green, orange, red).