Assalaam walaikum,
Your post has made me smile...
Usually, younger girls keep longer hair. As we age, most women will keep a shorter style. It is easier.
Now, if you are a young married woman ask your husband what he likes. Trust me, it makes a difference.
As for the teens..stay away from the fads. Do not let a hairstylist take out his frustrations on you with his scissors. Not everyone is Edward Scissorhands.
And keep a style that is easy to hold under a hijab...bangs are very difficult to keep neat under a hijab.