All good options. Choose what communicates your intent to your reader best. I can imagine one diagram with a clustered prototype or a deployed count, but I can imagine another that shows the load balancer and individual servers with names and IP addresses and so on. Figure out who needs to know what and tell them as clearly as you can.
A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi