Virginia = sweet natural flavor
Perique = piquant or spicy notes
Latakia = smokey and pungent
Cavendish = seems to have least Nic, can add flavor depending, or just smooth out the blend with unflavored.
Burley = deep, rich, nutty, nicotine
Orientals = spicy and or sweet notes
Plugs, cakes, coins, and flakes = some fashion of melding utilizing layers and compression. Most popular are the VaPa blends.