This comes up every year so I ask a question:
If you could fix copyright, how would you do it?
Here is what I would do:
1. All works must be registered in a government registry.
If it's not in there it's not copyrighted. If you want to register a work from before the law passes, you have to prove you own it under the current system. This would solve the orphan works problem -- if no one can prove they own it, it becomes public domain. Basically, ownership should be recorded like actual property with a proper chain of title. It would be published on a public ledger.
2. You must renew your registration every three years. The fee for renewal will be X% of the revenue from the work, where X = years since first registration - 5 (edit: With a minimum fee of $100 to discourage hoarding useless IP). First renewal is at 8 years. Your registration fee would be recorded on the public ledger.
If you want to continue to derive benefit from your work you have to pay for the privilege. After 105 years it will obviously no longer be worth it, but probably long before that. This would be reported like income taxes -- you self report your profits but if the government thinks you're cheating, they can audit you. If you have multiple works in one product (think Marvel movies) then all revenue goes to the oldest work (that way you can't avoid the fee by putting new and old characters together).
If you don't renew, the work goes to the public domain.
How would you fix copyright?