Most of them.... um.... let's take a look at a few of the ones i know.... Kimberly - Did a few tv shows, is in one now Zack - Did a few tv shows, and I beleive a movie Trini - Died Tragically Billy - Went into a dramatic depression after Saban treated him so bad. Jason - Quit fighting and exercising got fat because of it. Tommy - Hosted his own Karate Studio, Did Dino thunder, Joined professional fighting Kat - Did a few minor roles such as playing a corpse in a police show  Aisha - Did some TV & Movies Adam - Does lots of Anime Voices (Ichigo on Bleach is his best known) & stared in an episode of Power Rangers in Space, And Power Rangers Operation Overdrive & Plays in a band during his off time Rocky - got busy with his post PR didn't do Forever Red. Kira - Does her album, but has been in movies Scorpina - Had various Tv shows after ZyuRanger Rita Repulsa (Japan original actress) - Died. Lily - Went on to do other shows (Did one in New Zealand where she did some riskay scenes) Maya - Walked around in some movie as a foriegn student, nude and is still an actress and screenwriter.
To focus on the answer, the acting field is huge. I'd say they did pretty good. They search everywhere for new rangers each season. Actually they've started looking in Texas for the Goseigers. I heard that the Call for actors towards California will begin soon. Maybe I'll audition, But it's been a while since I did any TV spots. XD
Most of them didn't want an cting career but some do well such as Kimberly and Maya. Katrone was good but she retired.