I now see that the renaming functionality supports separate variables for year, month, day, hour and minutes (and seconds) - so it is easy to set up a preset for yyyymmdd_hhmm_custom text_original sequence number.extension. No explicit support for preserved sequence number - but can be achieved with something like basename and Replace "IMG_" with "" by using Kyno's replace feature. So renaming probably covers most use cases.
But a feature request is to be able to use variables similarly to renaming variables (current system date and time variables for year, month, day, hour, minute) in the Copy and verify feature to create a "Backup Name". Even better would be able to save several presets, e.g. import_yyyymmdd_hhmm_camera name1, import_yyyymmdd_hhmm_camera name2, etc depending on what memory card is imported. The yyyymmdd_hhmm is the current system timestamp of the import.