Service usage for Jira - Hide specific "Assignees" to users in group "Customers"

Hi,

we are using Jira also as a customer Interface.
However we would like to "hide" our top-developer names from the customers if such a Support ticket is assigned to them.

New Rule for Assignees field:
Hide "Assignees" to users in group "Customers" if Assignee is in (name1, name2, name3)

Ideally you would even be able to configure a place-holder that is shown
Hide "Assignees" to users in group "Customers" if Assignee is in (name1, name2, name3), Show "Development" instead.

Thank you for your help or possible ideas. I just purchased an unlimited license for your product ... maybe you could do this as a courtesy update. We have just updated to Jira 6.0.8

Thank you

br
Michael