It would be great to have the UninstallString (and QuietUninstallString) from the users ARP data in the registry. The EI Users Programs (EI_UserARP) does not try to capture this data. It is available in the registry: Computer\HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Uninstall\[ProductName] under UninstallString as well as QuietUninstallString.
This would be very valuable data, especially for teams performing software audits. They can silently uninstall software under the user profile if this data was more readily available.