It's a toss it up between Dark to light brown and blonde.
The dark to light brown is looks very natural as it sweeps down around your face, and doesn't stand out. However, I am also finding, because of your nice skin tone, the blond does offset your skin color, because the hair color itself, looks very natural.
Black makes you look a bit less soft, and no, not red or brown.
Anything close to natural (1st or 2nd pictures) is the best/most practical by far. You can dress it up or down, it can be made to look professional & you won't become the subject of unfavorable stereotypes.
That basic black is quite gorgeous though, I must say. If you can get your hair to be that shiny, people'd stop & take notice. It just looks so...healthy.