I currently use Github iTerm2 theme, specifically, the dark variant.
Here are some other resources for color themes:
Control Mac Keyboard Brightness - Programmatically flash the keyboard lights and control display brightness on Macs.
maclaunchmaclaunch - Manage your macOS startup items.
Brooklyn - Screensaver inspired by Apple's Event on October 30, 2018.
gon - CLI and Go Library for macOS Notarization.
mas-cli - Simple command line interface for the Mac App Store. Designed for scripting and automation.
Zero.sh - Radically simple personal bootstrapping tool for macOS.
macbac - Lists, controls and schedules efficient APFS snapshots for your convenience.
TinyLinux - Tiny minimum implementation of Virtualization framework to boot Linux.
MacHack - List of built-in tools in macOS that you probably didn't know about.