Member auto name is email need to be changed to some naming series

We are about to use the Member docType for farmer members. Currently auto name is set as email in docType. But our Farmers dont have email id.

  1. Is there any chance that a new naming series be created and used as auto name, in the ERPNext core code. If so can a github issue be raised ? As not all members have emails.

  2. If the above is not possible, if we do the customization in our App, i guess it will cause upgrade issues. What is the best way to move forward. Should i just create a naming series, set it as auto name in developer mode and export customization to my app ?

Pls let us know.