I am the current president of my (now former) university's chapter of Alpha Sigma Lambda... which is an honor society for nontraditional students. I recommend joining any/all honor societies that you are invited to. They are generally require minimal time commitments and it looks good on an application - especially if you are willing to accept a leadership role. My personal experience - applied last year, without honor society involvement and was rejected at both schools I applied to. This year, I joined 2 honor societies (and finished my degree, which certainly helped) and applied to 8 schools. I was invited to 7 interviews, attended 6, accepted at 5 schools - including my top choice that had rejected me the year before.
Bottom line, helps polish your application and lets you stand out a bit from the crowd. It's worth the membership fee 👍