NEEDS VS WANTS
The age-old question. Which comes first, Biblical teaching or meeting relevant needs? Stop shouting your answer; I can't hear you. The truth is, both are correct.
I'm always trolling other church's websites to see what they are offering in the way of small groups. Some are focused on discipleship. Others are focused on community needs. I want to share with you a few key things you can do that will help you decide.
Ask the Holy Spirit what you need to do.
Always start with this one. It makes life a lot easier for you. If the Holy Spirit is leading you in a particular direction. Then you can expect Him to show up in your small groups.
Don't try to be everything to everyone.
Larger churches have the staff and room to do more. But as a small to mid-sized church, you may struggle. Offer a couple of themes that are needed at the moment. You may want to take a survey, or you may even want to offer a slate of classes and tell them that you will only provide the top two or three that they pre-register for.
Make one about the Bible.
Always offer some Bible/Theology classes. Some people want to understand the Word better. Don't abandon them. As a general rule, I find they will attend more than one small group.
Blend the Bible into needs.
Review small group curriculum carefully before pulling the trigger. Are they addressing a particular need from the Bible's point of view? Some styles of curriculum lean more in the Bible than others. You may want to accent your lesson with your research. What does God say about marriage, finances, emotional health, and current events?
What are other churches offering and why?
If a church is older, it will probably offer some grief care. If the church is compromised of married couples, they may offer some divorce recovery. If the economy is tanking, churches will offer finance classes or even mini-classes to save money. (Anyone remembers those couponing classes from years ago?). Usually, you will see the culture and vision of the church reflected in their small group ministry.
What about offering one to the public?
Some small groups like Celebrate Recovery or Financial Peace University are designed to be offered to the community. If you feel comfortable, do one to the public, offer a marriage class, or maybe teach a foreign language. Offer it free or lost cost to the public and see if you can make some new connections while meeting a need.