Hi there,
Thanks for your suggestion. Email template names cannot be changed as the system uses the names to locate the appropriate email template to send (think of them like filenames). Changing the filename would mean the template could not be found and email sending to fail.
The ID numbers are not always consistent across individual WHMCS installations, so that wouldn't be a suitable alternative unfortunately.

The email subjects can be customised, so the template names are for internal reference, only seen by your full administrators. Perhaps if you can share more details of your use-case, there might be an actionable change which could be considered?