I don't keep up with rarity. Anyone who can direct me to a guide regarding rarity of games for newer systems? (NES,Genesis, SNES, and newer?)

If I had to take a guess, based purely on what I've seen in the wild:

NES:
Magic of Scherezade
Final Fantasy

SNES:
Chrono Trigger (complete)
Final Fantasy 3 (complete)

Saturn:
Guardian Heroes (loose)
Metal Slug (complete)

Playstation:
Final Fantasy Tactics (not greatest hits, complete)