So, I think this is both very useful and relatively simple to implement.
As the requirements person, you are in the driver’s seat when it comes to project scope.
There are a whole bunch of activities that make managing requirements a non-trivial activity.
You need tools to help you identify where the problems are and to support the conversations you need to have when negotiation scope/constraint issues.
Lastly, you need to understand your local conditions. Do you align to industry averages? Are you more dynamic? More stable? What data do you have to support your assumptions?
Go get the data, starting next week.
Possibly it’s there in past project reports.
But build up your own repository of knowledge and take it with you. There is a lot of variation in our industry and one person practicing some excellent techniques can make a big difference.
And as the six sigma people out there know, having the numbers helps you win your arguments.