Context Sensitive Selection of Parent in Forms

As a Model Builder an Planning user it would be great if the Parent Selector of a Form could be context sensitive. Forms are used to create new Elements in a numbered list which often need to be dynamically attached to a parent. E.g. I want to create a new position ins a cost center looking at a specific cost center. Currently I need to reselect the Cost Center in the creation process which can be tricky in long lists.