rahu ketu
No planet is entirely bad who so ever it is on the subject of life and its effects on to life, in fact its time or time period which make one good or bad as per the respective mode or association their in, so is the case for Ketu.
Ketu and mars belongs to same category while to inflict in life with a difference of pace, mars is super fast to interact with where as Ketu has its own pace and game plane for life.
If Rahu or Ketu placed in zodiac at Kendra may be taken as 4th, 7th, or 10th house happily including very first and links the lord of trine houses in any of its mode then they inflict extremely fine result or out come in their reflective period in life, as it form a kind of raj yoga, very auspicious all the way.
Much other yoga also has the similar impact on life through Rahu & Ketu.
One can expect any thing good as inflicted by the benefic planets by Rahu and Ketu n their transit but based in their zodiac status and forming yoga’s their.
May god bless all.
Thanks please.