The most interesting die is the 11/12/17 which was reground and has enough differences that Sheldon gave it a different number, but even he recognized them as the same die in just a significantly altered die state. ps I use Sheldon nomenclature which Noyes has done. Breen used his own, but it's not used frequently.
Obverses 4 and 8 of 1801 are considered the same with 8 struck before 4. This is one of my coins which is technically a S-221, but which I believe is in a die state found on the later die state. Breen speculated on the opposite. The last two die states of S-221 may have been struck after the obverse was reground. This appears to be the second to last die state of the S-221 before the CUD over STAT is developed.