https://www.visualstudio.com/en-us/docs/work/process/manage-process
Create from core process
Only inherited processes can be customized
No data is lost if project is reverted back to core process
https://www.visualstudio.com/en-us/docs/work/process/customize-process-field#add-person-name-or-identity-field
Custom work item identity fields
Users can now add custom identity fields to their projects. This allows users to define additional fields like “Assigned To”, which will give users a people-picker experience to select people as the field value. In this initial release, all users in the Team Services account will be valid values for each identity field.
https://www.visualstudio.com/en-us/docs/work/scale/review-team-plans
Delivery Plans help you drive alignment across teams by overlaying several backlogs onto your delivery schedule (iterations). You tailor plans to include the backlogs, teams and work items you want to view. 100% interactive plans allow you to make adjustments as you go.