This topic about organizing your instruments Reminded me how nice it would be if you could color the instruments.
The color would than appear both in the pattern and in the instrument list.
I also still miss a an icon next to the instrument name with which you could mute/solo instruments and an light blinking as the instrument is played. (Useful to see if the instrument is used or not and cool.)
https://forum.renoise.com/t/organize-your-instruments-in-a-song/18142