Ok, you have articulated a couple of reasonable approaches the Trump team might take. One problem might be that even after being told about the classified documents, Trump resisted returning them and allegedly took steps to prevent a thorough search even by his own attorneys. As to the fact that others have done as bad or worse, I agree with you, but that is a political argument, not a legal one. Selective prosecution claims are very difficult to win in court.
In other words, they said they're classified...Trump said...no, they're not...the removal to Mar A Lago was a way of declassifying anything that should have straddled into the thousands and thousands of papers.
Remember, the NARA had "0" knowledge of what he had.