Have we come to an agreement about the currency 'issue'? I think it would be best if we only have one name for the coins (Gold) and instead have different values stamped on them (1,2,5,10,20,50,100). If we start giving them different names like Drakes and Septims I think it will be a bit confusing to keep up with.
The naming scheme I suggested was simply for the people saying "This wont fit because it's not lore compatible."
The terms Copper, Silver, and Gold could precede the word Septim or Drake (which would be equal to each other).
You also have to remember than in the old days you couldn't just stamp a number on a coin and give it that value. That only works when there's a "Gold" standard where each coin represents a set amount of a precious metal in a vault somewhere, and you can exchange it for said precious metal at anytime you want. What gave a coin it's value was what it was made of.
I think using a Copper, Silver, Gold system as a set of "Septims" or "Drakes" would work best. You could say "I handed him 100 coppers." or "I handed him 100 copper Septims," or "I handed him 100 copper drakes." Which would be the same as saying "I handed him 10 silver Drakes," and "I handed him 1 gold Septim/Drake."
That way we don't have to worry about getting Septim, Drake, and Gold mixed up. We just attach Copper, Silver, or Gold to Septim, Drake, or nothing.