Does flux "broadcast" it's color changes anywhere that would be scriptable? For example, using a dark terminal theme gives the wrong effect in darkroom mode. (90% of the screen is red). So I'd love to be able to script the changes and adjust that (and potentially other) settings. Or maybe a plugin architecture? :D
It might be less than ideal, but I cloned my profile in iTerm and set it to use lighter colors (Solarized Light) and just switch to it when I kick on darkroom. You should be able to map this profile change to a keyboard shortcut, depending on what you're using, to make the switch a little easier.
If you use terminal full-screen (like myself), you can also invert screen colors[0] whenever you switch to it in Darkroom mode.
This makes your dark terminal background, that became light thanks to Darkroom mode, dark again.
It's a little bothersome to invert colors every time, but I guess I'm settling on this for now. I use powerline in tmux and vim, and there doesn't seem to be a quick way to configure it with light-background colors (and changing terminal color scheme doesn't affect its looks).
[0] Inverting colors is toggled with ^⎇⌘+8 by default. You may need to enable this shortcut in keyboard preferences.