At the moment when you realize you made a mistake with a report or you don't remember the criteria you created it with, the only way is to delete and create it again. It would be great if you could edit them instead.
It would also be useful to be able to duplicate and edit an existing usage report as an option from the menu - e.g. to set up the same report for a different provider or select different date ranges. At the moment we have to set up a new usage report from scratch for each provider. We can duplicate & edit existing records from the menu in the Koha reports module and in Acquisitions for funds, etc. The ERM module seems to be the main area where you can't easily duplicate an existing record (usage reports, licences, etc)