It would be good if Mendix extended the functionality of XPath. I suggest adding: lower-case (), upper-case () and translate (). But there are others.
It would also be good to take a look at the features of XPath 2.0. I know that in Mendix, it is not exactly XPath that is implemented, but it would be brilliant to provide the equivalent. In fact, it would be more transparent for a new Mendix developer to switch from one language to another.
Anothers functions : currently it s not possible to execute a IN query... like :
[EBCC.Employee_BPoffice/EBCC.BPSyncOffice/OfficeID in ($BPSyncOfficeList)]
Problem with the apostroph too.