@TomScott - The problem is that not all developers will be raising tickets, some will just reauthorise the connection again.
Did you check this thread below? @Cliff_Field had a thought that if the User reset their Password, would it affect the Access Token?
If you are saying that the majority of errors are on the client side, then what is the correct procedure in handling the tokens? If you have a Cron Job running every 24 hours getting and storing the tokens then that would be sufficient.
It seems to me that developers should be logging all the token requests and responses. Then if the issue occurs again that will give you a better idea where the problem could be.