Re: don't forget the habitable zone of the galaxy . . .
Just something else to further limit the likelihood of -- Earth-likeness.
"several hundred billion" main-sequence (main-sequence = possible Earth-likeness) stars? I demand a recount. According to this source, there are currently about 100 billion stars, or less. Very few are in the galactic habitable zone, and fewer still are main sequencers.
Also, no colors yet, but dino skins have been found.
Gotta go type,
Dan