1. Details & Summary behave a lot like the accordion design pattern, only just the basics. Could you layer on functionality, like a group of details elements in which only one can be open at once?
  2. Can you progressively enhance Details & Summary to add custom styling and animation?
  3. These elements don't work in Edge. You could have a look at the polyfills out there and perhaps build your own if you'd like to have a go at it.