Change Request: adding some filters

This is great plugin.
However, there is no possibility to adapt the execution to users’need from any other plugin.
My main concern is related to backup file delivered by mail.
In my mind, sending in clear text the users table is not very secure, even if the passowrds are enciphered in this table. And so, I propose to add a filter to the list of core tables to be backuped.
Another filter could be at the end of the production of te backup file, before sending it, allowing to perform some encryption.
Thanks.