My pick is Elian. I think they’d sell millions and never have them used. Why let the “souvenir” money go to Franklin Mint or some country like Barbados?
If you are talking about a good money making thing, pro wrasslers or pokemon characters on anything will sell.
A good cuz it’s history thing - the fall of the berlin wall.
I think we should have stamps for former presidents, like Jimmy Carter, once they leave office.
The old rule that they have to be dead was an 18th century worry about Washington being crowned king. With the latest batch, that’s no longer a concern.
At least, the day a president is dead he should be planned to appear on his next “birthday”.