If you have a limited number of groupings, it will likely be simpler just to
make a report for each -- you can copy the basic report and modify it.
Different groupings would imply different data in the Controls in the Group
Headers and Footers, so that sort of "customization" would be more
extensive.
I have had good luck giving users some basic training in creating reports,
and giving them a database for reporting, linked to the tables.
Clearly, you can do some very detailed and complex things in a Wizard, but
there is a tradeoff in implementation time to be considered. The tradeoffs I
have seen people make on user-customization, in order to keep the
implementation time within reason, left the user with so little flexibilty
that the customization was simply not used.
Larry Linson
Microsoft Access MVP