In terms of Rules (Automations) and Forms, I could see value in having the ability to associate criteria from drop-down type Custom Fields to specific users. You would need a new section within the Custom Field editor to associate each drop-down to an existing user in Asana. This would have to be optional but I could see where it could be valuable beyond just Custom Fields that represent people.
The gain would be to make sure individuals are added (or potentially even removed via Rules) as an Assignee or Collaborator when a Custom Field is met.
Through Rules there are ways to accomplish this today, but you have to set the Rules manually for each user which eats into the project limit. The real value I see is being able to ensure all the right context is applied through a Form entry.
@Phil_Seeman if this is something that falls outside of scope, I could see it as a great Flowsana add. While I want to use options like “add submitter as collaborator” I run into the issue of having multiple domains without our company. If users don’t list the right email then things aren’t assigned properly, it at all. This could solve for that, among other things.