The "Set Up a Cluster Node" page is a mite confusing.

Change wording: "Your Confluence host has multiple network interfaces suitable for clustered communication. Please select one to use." to "Choose the network interface Confluence will use to communicate with the other nodes in the cluster."

Replace two headings "Join a Cluster" and "Create a New Cluster" with "Configure Cluster", with a place to enter the cluster name (laid out like it is currently under Create a New Cluster), then two buttons: "Join existing cluster" and "Create new cluster"

If "Create new cluster" is selected, then take the user to a new screen to select the type of database (use the regular database setup action, but disable the option to choose an embedded database)