Which ones would you like to see? We're always looking for new use cases to support.
For what it's worth, if you have an onUpdate trigger on a Firestore database, the event you receive has the before & after state of the change, which would include field-level changes: https://firebase.google.com/docs/functions/firestore-events#...
Is there a specific use-case that this doesn't handle for you?
Note: Work at GCP, not on Functions.
My use-case is simple. Want to get my CF triggered if the value of a particular field in a doc changes. Thanks.