The copyright term for works owned by a corporation should be cut wayyyy down. I'm fine with a long copyright if it's owned by a person, but corporations shouldn't be able to lock down things that are older than like 20 years old. People shouldn't be forced to buy a long discontinued console in order to legally play a old game.
Well then make it impossible to transfer the copyright. In most jurisdiction it's not possible anyway. You can only licence it, not transfer.
I guess it might be difficult to figure out shared copyright in teamwork, but indie teams work just fine, and it's still a better option than corpus sitting on a golden pile of IPs.
I like the idea of non-transferable copyrights a lot. That would make the "this is motivation for innovation / just protects inventors and artists" claim a lot more believable to me. I don't think it should even be passable to descendents/"estates".
And maybe also disallow "our employees' inventions/creative work copyright automatically goes to the company" clauses. This would be... Waaaay more complicated to sort out, but still worth thinking about imo.
That sounds a good solution to me, and it would fix many of the issues with modern copyright law. Although I feel "lost profits" for companies would mean that this would never be implemented.