OP here. Unfortunately the ansi palette is pretty limited so I didn't have a lot of flexibility in the color choice. That said, this can definitely be improved. I can work on it if people find it useful.

In the meantime, it's very easy to tune the colors your own: just modify this line https://github.com/draios/sysdig/blob/master/userspace/sysdi... in your local version of the script, using this as a reference http://misc.flogisoft.com/_media/bash/colors_format/256_colo....