'Time to start action' custom perspective

Hi guys! I just downloaded OmniFocus 2 yesterday and I’m very impressed with the capabilities and customisations on the app. Anyway, I have an idea here to create a custom perspective which shows actions where the current date/time minus the estimated completion time is less than the due date/time minus the estimated completion time. Basically, it’s a list of actions where if you don’t start now, you won’t be able to finish the actions in time based on the estimated time. I find this quite useful for me to determine which tasks to start first to avoid rushing in the end.

If anyone has any idea how to implement this please do comment! Thank you!