Update README.md

Author: FZambia

README.md

@@ -1,4 +1,4 @@
-Centrifugo is an open-source scalable real-time messaging server. Centrifugo can instantly deliver messages to application online users connected over supported transports (WebSocket, HTTP-streaming, SSE/EventSource, GRPC, WebTransport). Centrifugo has the concept of channel subscriptions – so it's a user-facing PUB/SUB server.
+Centrifugo is an open-source scalable real-time messaging server. Centrifugo can instantly deliver messages to application online users connected over supported transports (WebSocket, HTTP-streaming, Server-Sent Events (aka EventSource), GRPC, WebTransport). Centrifugo has the concept of channel subscriptions – so it's a user-facing PUB/SUB server.
 
 Centrifugo is language-agnostic and can be used to build chat apps, live comments, multiplayer games, real-time data visualizations, collaborative tools, etc. in combination with any backend. It is well suited for modern architectures and allows decoupling the business logic from the real-time transport layer.
 
@@ -28,11 +28,11 @@ The core idea of Centrifugo is simple – it's a PUB/SUB server on top of modern
 
 The hard part is to make this concept production-ready, efficient, flexible and available from different application environments. Centrifugo is a mature solution that already helped many projects with adding real-time features and scale towards many concurrent connections. Centrifugo provides a set of features not available in other open-source solutions in the area:
 
-* Efficient real-time transports: WebSocket, HTTP-streaming, Server-Sent Events (SSE), GRPC, WebTransport
-* Built-in scalability with Redis (or Redis Cluster, or Redis-compatible storage – ex. AWS Elasticache, KeyDB, DragonflyDB, etc), or Nats.
+* Efficient real-time transports: WebSocket, HTTP-streaming, Server-Sent Events, GRPC, WebTransport
+* Built-in scalability with Redis (or Redis Cluster, or Redis-compatible storage – ex. AWS Elasticache, Valkey, KeyDB, DragonflyDB, etc), or Nats.
 * Simple HTTP and GRPC server API to communicate with Centrifugo from the app backend
 * Asynchronous PostgreSQL and Kafka consumers to support transactional outbox and CDC patterns
-* Flexible connection authentication mechanisms: JWT and proxy-like
+* Flexible connection authentication mechanisms: JWT and proxy-like (via request from Centrifugo to the backend)
 * Channel subscription multiplexing over a single connection
 * Different types of subscriptions: client-side and server-side
 * Various channel permission strategies, channel namespace concept
@@ -41,8 +41,9 @@ The hard part is to make this concept production-ready, efficient, flexible and
 * Online channel presence information, with join/leave notifications
 * A way to send RPC calls to the backend over the real-time connection
 * Strict and effective client protocol wrapped by several official SDKs
-* JSON and binary Protobuf message transfer, with optimized serialization
+* JSON and binary Protobuf message transfer, with optimized serialization and built-in batching
 * Beautiful embedded admin web UI
+* Great observability with lots of Prometheus metrics exposed and official Grafana dashboard
 * And much more, visit [Centrifugo documentation site](https://centrifugal.dev)
 
 ## Backing