I dont know much about the TP-LINK I just glanced at »www.tp-link.com/us/products/deta ··· R470T%2B
but your diagram is sound. Assuming the TP-LINK router can route across all its ports, you can do what you want. That said, traffic between your two internal subnets will flow through the router and might be limited by the performance of the device. If the TP-LINK cant route across all its ports, youll need to replace it with a router that can or replace your unmanaged switch with a managed switch that can also do routing (and youll plug AP1 into this switch instead).