Description:
Since MySQL Router is useful for load balancing and failover MySQL connections and 
it is useful for not only Replication but MySQL Cluster, so I think it should change the naming of connection modes.
How to repeat:
There is no description since it is not a bug.
Suggested fix:
Current                Suggestion
------------------------------------------------
mode = read-write ---> mode = first-available
mode = read-only  ---> mode = round-robin
□ mode = first-available
[use case]
 Replication with Single Master Mode (Failover the Master)
□ mode = round-robin
[use case]
 MySQL Replication Slave with Single Master Mode.
 MySQL Replication Multi Master Mode.
 MySQL Cluster