This script adds level-ups (in gold) and level-resets (in dark grey) to the WaniKani heatmap widget.
I love tracking all sorts of data and was disappointed to find no level information on the Heatmap.
It’s available on Greasyfork.
I haven’t added any support for the different colour schemes, but you can change the colours by modifying the values at the top of the script.
Here’s how it looks:
Enjoy!