EDIT: This is now integrated to Photon as the Neutral theme.
I did this a while ago, when theming was first introduced. I wanted a dark theme that wasn't black, and also not tinted.
{"other":{"black":"#000000","white":"#ffffff"},"primary":{},"zinc":{"700":"#484e57","800":"#373b41","900":"#282a2e","925":"#202225","950":"#1d1f21"},"slate":{}}
I don't know. Just "Gray" is also fine by me.