We strive to maintain a very lean organizational structure because complex organizations require maintenance, staffing, rules, and energy. Also, large organizations can be a stumbling block to those who are attracted to positions of power. Lastly, by maintaining a minimal organization, we feel that we give the Holy Spirit greater flexibity to operate in a living organization. It is possible to squealch the Spirit and we strive not to do that by being flexible and minimalistic regarding what we, as mere humans, add to the foundation of Christ.
To maintain a lean organizational structure, we minimize the number and complexity of tasks we undertake corporately. We encourage subsets of our church to undertake projects together on an informal basis. For example, a Small Group may undertake a project to help out the neighbor or relative of one of their participants. As another example, a sub-set of people may organize the raising of money from the Large Group to sponsor a larger project. So again, we encourage inventiveness, creativity, and spontaneity in the body of Christ but we limit the responsibility of the church as a whole in order to minimize the organizational structure.
The requirements of the organizational structure for the church are as follows: (1) Scheduling and making arrangements for the monthly Large Group meeting, (2) Managing the Small Groups (establishing new ones, helping struggling ones, etc.) The people responsible for those requirements are the Small Group leaders, operating together in cooperation with each other. For the most part, anyone wanting to become a Small Group leader may do so. However, we distinguish between that role of leadership and that of "spiritual leadership", i.e. the responsibilies of what is often referred to as "elder", "shepherd", "pastor". The position referred to by these latter terms is not something that we select through a vote or any type of ballot process, which is a method used by larger institutional church organizations. We have no need for those formal processes and take a completely different approach. You can read more about that approach here.