Creating a Mikrotik Network \"upgrade\" ready

I'm starting a Mikrotik network. I think this project called a VPN network. The topology is attached. What i need : - configure all the network - all secondary router will act as bandwidth limiter - user database will be centralized to primary router - primary router work only to manage user databases - consultation about what router/hotspot fits - Script needed for increasing/expanding network (adding new router/hotspot) - user manager integrated - prevention from any common problem