Regarding distances between the stars, and the the light shed upon planets, the Alpha Centauri system is pretty close to the requirements that you want. Here is some useful information summarized from the wikipedia page onabout Alpha Centauri, (https://en.wikipedia.org/wiki/Alpha_Centauri#View_from_a_hypothetical_planetView from a hypothetical planet)
-Alpha Centauri A ("A") is 1.5 times as luminous as the sun, and B is 0.9 times as luminous as the sun. -A and B have an orbital period of 79 years (a human lifetime) where they go from 11 AU apart to 35 AU apart. -For a planet circling A such that A is the same brightness as our sun, B will appear to be 190-2500 times as bright as the moon. -For a planet circling B such that B is the same brightness as our sun, A will appear to be 580-6900 times as bright as the moon.
- Alpha Centauri A ("A") is 1.5 times as luminous as the sun, and B is 0.9 times as luminous as the sun.
- A and B have an orbital period of 79 years (a human lifetime) where they go from 11 AU apart to 35 AU apart.
- For a planet circling A such that A is the same brightness as our sun, B will appear to be 190-2500 times as bright as the moon.
- For a planet circling B such that B is the same brightness as our sun, A will appear to be 580-6900 times as bright as the moon.
That last figure (6900 times as bright as the moon) is equivalent to 1/70 as bright as the sun. While that is bright, that is the equivalent of our own sun from 8 AU away, which is between Jupiter and Saturn. Bright enough to keep you up at night but not bright enough for photosynthesis or turning a planet into Arrakis.
