Currently XMS doesn't prevent wrong configurations, e.g. drop-down lists are not restricted by any control of availability for instance.
An important use case is the selection of subject and measure for data presentation which should be restricted to the available combinations...
Another example is "use latest data" which forces chart to be either a bar or a symbol chart, but the user can still select line chart as default presentation; this is confusing to the user.
There are many more use cases.