Toby Crawley from Bob McWhirter's team has developed a small library for creating nicer feedback messages when xml parsing errors are found, based on analysis of the xsd.[1] He has done some work on integrating this library into WildFly for parsing the server/domain config documents and has proposed adding it in.[2]

[1] http://post-office.corp.redhat.com/archives/jboss-tag-public/2016-June/msg00016.html
[2] http://lists.jboss.org/pipermail/wildfly-dev/2016-July/005280.html