Good question. While I personally would not consider "suggesting copyright overall is now meaningless" to be a failure[0], there's no way in hell anything that might even remotely harm industry revenue would ever make it through Congress, European Parliament, and/or the Japanese Diet; much less survive challenges in the court or WTO. So the only reforms I can actually suggest are marginal things like this.
Anyway.
First you need to legally define the kinds of licenses we care about. There's a bunch of very good reasons why permission can't be sold, so we want to make it clear that we're only talking about things that function like a sale. That is, one-time purchases of works that are downloaded to a device and whose license grants fall within normal use of that work. This is the sort of thing that needs to be drafted water-tight because the industry absolutely will search for excuses to not comply with the law.
Second, we need to define how a transfer can be done and who needs to honor it. This has per-work and per-service considerations, especially in games[1], which have anticheat and toxic player removal. There are times where a copyright owner has a legitimate interest in taking away the thing you bought because you are ruining the experience for everyone else. So we need carveouts for our carveouts, both of which need to be carefully drafted to not interfere with anticheat.
And this is only considering digital-to-digital first sale. That's easy to do because the systems already exist to revoke and delete your ownership over digital copies of works; you just aren't allowed to use them for first sale purposes. We're ultimately just dictating that certain kinds of DRM license files have a legal mechanism to transfer between owners.
Physical-to-digital schemes like the IA's Controlled Digital Lending pose an additional problem: there's nothing to physically enforce the destruction or disabling of the physical copy when you convert it to a digital one and lend it. The book doesn't refuse to open because someone has it open in Adobe Editions. Everything is done on the honor system and there's massive incentives to cheat CDL. The discovery on the IA lawsuit showed that they basically had never complied with their own legal theory. They had partner libraries who were counting copies of books as digitally loanable without actually taking them out of circulation, and when IA had discovered this on their own, they never did anything to take that library out of the system.
An actually legal CDL regime would need infrastructure to support itself. I'm talking legally qualified DRM banks that could lock up or burn books in exchange for DRM limited files that accurately represented the time in which the physical side of the book was inaccessible. That's... still extremely complicated. Actually, screw CDL. If we're talking about amending the law, there is a far easier way to go about fixing the problem with ebook lending: Book Communism!
Compulsory licensing is a scheme in which the government sets the price of a specific kind of copyright license. If you pay that amount of money to the copyright owner, you automatically have that permission, they can't say no. Naturally, copyright owners would liken this to theft, but they thought your dad's VCR was a home-invading rapist[2], so I don't consider their opinions on the subject to be meaningful. The idea is actually pretty straightforward: having a government-set license price makes licensing a lot more straightforward. Creative work owners can't make silly demands of users or withhold shit because their """strategy""" that quarter was to keep something off the market or sell exclusivity[3].
The specific imbalance that IA tried to fix with CDL is that libraries, being public services run by local governments, do not have negotiating leverage for favorable ebook lending terms with major publishers. "Just lend out physical books digitally" fixes the problem for libraries but the infrastructure needed to make this not unfair to authors or publishers is silly. Why can't we just have the federal government say, OK, we'll sell licenses in which any library can pay $X to the owner of a given book and then digitally lend it out Y times or for Z days? The Copyright Office or some administrative judge can determine fair values for X, Y, and Z.
[0] For one thing, if you are a small artist, you effectively do not have copyright protection because the enforcement costs for a single infringer greatly exceed your total revenues. Copyright is already a failed system.
[1] For example, if reselling whole accounts is legal, then I can buy hundreds of accounts, play the game I want to cheat in on each one, and switch accounts whenever I get banned.
If reselling individual licenses is legal, then after I get banned, I can resell the license - which continues to remain valid - and get my money back so I can repurchase the game on a new account with a fake identity.
[2] https://en.wikipedia.org/wiki/Jack_Valenti#Valenti_on_new_te...
[3] A related wrinkle in the CDL story is that publishers really, really hate libraries. Not because they let people read books for free - in fact, library circulation is actually really good advertising for sequels that won't hit libraries right away. The problem is that libraries are run by book fans, so they're going to recommend books they like, not what the publisher needs to sell that month.