I only base rarity on what I have and that can lead to a poor assessment of rarity. In my case I rank rarity this way (1 is rarest):
1. 10c MG type I
2. 15c MH
3. 1p MM, all 1p with boundaries, all 50c, a few austrian 30c, 3c MM
4. the remaining 10c Type Is and the remaining 1p top and bottom overprint without boundaries
5. all remaining large format (25c, 30c)
6. 2c, 3c, 20c JMG and 20c MG
7. 10c type II
8. 5c offset and 1c
9. 5c typo
Mi bias is for used and on cover only are useful to measure rarity since the mint ones are remainders. I have a notable example: my almost complete sheet (89 of 100) of the 30c MH 1E2 is for a stamp for which I only have a handful used, yet I have dozens of the 30c MH 1E1 used. I will post here once I get some responses from the Argentinean forum.
The above ranking is slightly different to the table below because I have additional stamps in a stock that I have not counted, and because I am 'not there yet' in measuring relative rarity correctly. Here are the stamps I have as singles and small multiples (four or less), used and mint. I have not counted the large number of remaindered blocks because these create a lop-sided count...I will think a bit more about this issue.
