what editors/tools for XML users but non-specialists provide most advanced entity management facilities

Hi,
as per the subject line. My general experience is that for
non-specialists entity management is a non-issue but I was wondering
if there any of the tools that are considered as XML tools for people
that need to work with XML but are not specialists that still provide
advanced entity management? Has anyone any favorable reports to make
about specific tools?

Cheers,
Bryan Rasmussen