You make it all public domain. It's been over 20 years, well past the founding father's original intent for copyright. The perpetual copyright garbage that exists today is culturally toxic and isn't seen in any other field of work. Should builders get paid on buildings that keep standing? Highway workers on roads that they make? No? Then why the hell should creatives get special treatment? Look at the house of mouse and the crap they've pulled. The fact that you can't take something you've loved for over 20 years and make derivations on it is theft from the public in my eyes. People being born today most likely won't be alive by the time it goes into the public domain. Think about that.