"Simplicity Sells"

That would be built on the file and database management modules.

Thank you David and Garry! .. and all others for great debate/ideas.

@Susan, very nice and IMO to the point list of features.

@Ryan, Create a web app/website, package it for re-use? That would be AWESOME!

I agree with Susan, the biggest current stumbling block is the users; but I agree with Ryan’s point that installations is a sixth area. Yes, it would build on #4 and #5, but then so does #2. Particularly if we think of these as "functions that should be kept in mind when developing MODx", it needs to be a distinct entry.

So:
#6 Add-on management

I break down "management" in all 6 parts to mean:

#A creation by authorised users
#B access by authorised users
#C amendment by authorised users
#C removal by authorised users
#D assignment of authorisations
#E organisation and labelling
#F applicability (use and reuse)
#G import
#H export
as appropriate. Is anything missing in this list?

EDIT:
#I approval by authorised users