Currently the record 'event' object just contains the name and value of the event. To be more useful, it should also provide some 'context' information, such as what triggered the event (e.g. the ID of the parent record when triggered by a 'New'). If triggered by URL Action, then the context could include the query/parameter string provided. The data-event code could then process this string in whatever way it wished, thereby allow more logic/options for pre-filling forms that are created.