Looking at your space and your application, you will hopefully be able to focus on one end of this range and easily select a camera. However, your application may have needs that span the entire zoom range (e.g. a long Boardroom table that is also close to the camera). In this case, you will have to compromise on one end or the other but still try to find a camera that offers the best compromise (e.g. a 5-70 degree HFOV range would provide good headshots and capture all but the closest seats to the camera equally well). Take a look at this example presentation from HuddleCamHD reviewing the fields of views at corresponding differences depending on the optical zoom of the camera.