"admin ui'? Do you mean the web console (http://loclahost:8080/web-console)? That is an orphan and has not been updated for ages. Most people use a text editor, edit the XML configuration files by hand, and copy them to the deploy directory. Also, if I recall correctly, if you use the web console to create, say, a data source, that data source disappears when you restart the server.
So jboss does not have a good graphical user interface for admin operations? We are now looking for an application server. We started with glassfish and now we are checking jboss. It could be so helpfull if jboss can provide an easy way for configuration, deployment and performance just like glassfish has and many other app servers.