About adding date attributes to relationship

So we recently had a discussions on dates in this thread: https://community.metabrainz.org/t/adding-start-and-end-date-attribute-to-relationships/683222/25

And I can think of two options that we can do:

  1. Use ISO 861 as the date format and create an attribute named date. To show this as start date end date, we would need to parse this format into readable format to display to the users. We would also need to parse the input taken from users into this format.
    This will reduce the number of attributes to just 1 but increase complexity in the backend.

  2. Make different attributes for each of these : Start date, End date and Date(for relationships that do not need a time range)
    This will make more sense from a developing point of view as less complexity but can branch out to other different problems as mentioned in the discussion above.

Please let me know which of these should be preferred or any suggestion that you might have, so I can work upon it.