In general you will be removing it.
If you did want the contents captured and sent to all users there are options for fill existing users and fill new users once the package is in Casper Admin, without the use of either of these items selected user folder contents are probably completely meaningless and should generally be removed.

It really depends on what the files in your user folder are. Some files can be deleted and will not affect the installation of the application. Others may be required.

This is an example of an .xml file in my user folder. The .xml file contains server information, so removing it is not an option!

In Casper Admin, I select the FUT and FEU checkboxes to add this file to new and existing users folders. By doing this, the user folder named steve (pictured above) is not copied to the target computer.

Hope that helps.

In most cases, you will want to use a snapshot in composer to investigate what files are being put where via the vendors installer. You won't want to recreate the whole installer, but rather just supplement anything that you want to add to the process.

If there are files that must be included in each users home folder for the solution to function, the DMG package with FUT and FEU options are a way to achieve it.

Need to avoid that if it's .plist files though. If you need to manage keys in plists, you can use custom configuration profiles.