Just created a pull request.Can you go through Github?
In principle a good idea, but please make the colors really really distinct for us poor colorblind folk.Would it be a good idea to have an indicator a city has clean power? My idea is that the normal yellow thunderbolt is shown if you have normal power and a green thunderbolt if you have clean power. Dirty power in DoC has a much bigger gameplay impact, so I think it is nice if you can easily see which cities are affected by dirty power and which ones do have clean power already. It also saves the effort to manually check which cities make use of the clean power or Itaipu Dam and which cities are not affected by it (and require an hydro dam or solar plant).
Speaking of clean power, is it possible to have 'clean power' plants (e.g. hydro plants) make coal plants go obsolete in that city so the umhealth penalty is no longer present?
This confusion underlines the importance of signaling the presence of green energy in the interface.That is already what is happening. The building remains, but you do not get any unhealth from power anymore.
No, that should prevent issues. I had problems with the smaller game font files in the past if I added just a single font symbol. For some reason it disappears when you add two.