include more than one field in grouping headers
When grouping, only the field that is selected for grouping is displayed in "header". However, other fields are available to display in the header of the group that are common to the grouping field. E.g. Car repair/services. A service is needed on a car. The car name is used for grouping, but also the model, year, color, VIN are also attributes of the car, rather then service. The various services are displayed under each car. In the current set up, only one of the car-related fields, model, would be in the header. It would be nice to have model, year, color, VIN in the header, and then only the service (with service related fields such as date, repair shop, description) shown under each header.
I have the same need for a project. If you don't mind some of the data wrapping, you can create a formula field to concatenate the data you need and then group on that instead. I haven't figured out how to insert a CRLF to format it, however.