Groups that stick together, grow together. Relational growth within a small group context almost always leads to spiritual growth.
As we deepen our connections, our trust in one another grows, allowing us to be more authentic with each other and more open to correction from one another. When that authenticity and correction is prompted from and rooted in God's Word, spiritual fruit is the result.
Groups are often tempted to shortcut the "fun" times because they want to get to the "deeper" study. Unfortunately, without relational connections, most change is either intellectual or surface only and very temporal. Groups that spend time getting to know one another are far more likely to produce long-term, Spirit-prompted life change.
One of the best practices a group can use to get to know one another is simply asking and answering questions. Well-crafted questions have the potential to create laughter, invite introspection and break down walls within the group. I recommend groups should spend time every week simply asking and answering questions about one another. Done consistently, this seemingly benign practice will reap a spiritual harvest.
Good questions can be found anywhere. The sample below is from Pinterest. The more you search for other people's questions, the more you'll understand which ones work and which ones don't. Eventually, you may be able to write your own. You really only need 1-3 questions per meeting. The image below is a great start!