> May you please describe what kind of feature you want to introduce and
> explain why it is useful for other Org mode users?

The feature I want to introduce is to allow the headline parameter to be a function for the `file+headline' target for the `org-capture-templates'. The function would take a list of headlines as a parameter, and the user would be able to pick a headline it wants to reuse or create a new one by returning a string. This makes it possible, for example, to pick a headline dynamically based on the current time (like in my case) to add an entry, or the user could implement a function that prompts with existing headlines to choose from.