VPN Mesh box limit

Is there any plans to increase the VMN mesh limit, or options to do so without moving from the business to the professional plan. I have the desire for all my family's devices, 4-6, boxes on the VPN mesh and it seems the max on my current set up is 3. I do not need all the features of the professional plan. Just the desire to have a greater number of boxes in the mesh. 

Thanks,