I don't have an answer, because regardless of what some experts believe, there will be chaos if total transfer freedom is allowed, but there needs to be more clarity on the transfer system. I think the hardship rule is good, and I understand defining what exactly that means is tough, but I think things such as playing time limits is a good place to start. If a guy logs less than X minutes in games, or plays in less than Y games, then allow immediate total freedom to transfer. Any change in HC should also warrant such changes.
There's no such thing a perfect system, but there's no doubt ways to improve the current "rules" (in the loosest meaning possible).
There are lots of good ideas out there. Some of them are more labor intensive for those approving the waiver (medical, distance look-ups, or playing time/games played).
I bet the NCAA would want to make it easier and a blanket system for everyone without having to go case by case. (Which is probably a lot of man hours)
My suggestion would be to simply have free transfers but lose a year of eligibility each time you transfer. Since each athlete gets 5 years to play 4, after their first season they would still have 4 years to play 3. If they decide to transfer, they get a free pass and still have 3 years to play 3.
However, after they play the next season, they will only have 2 years to play 2 left. If they try to transfer again, they lose another year and at their 3rd school they would only have 1 year left.
It would deter multiple transfers without punishing the first transfer since often there are good reasons for that first transfer.
It could also be applied to the grad transfer process and possibly cut down on them. (Or have no effect)