Delta makes some good points about treasure hoards in this post and its comments.
I already adopted a 1,000 cn per stone standard in Game XYZ. The transition to silver standard I’m not so sure about, but there’s nothing keeping me from doing it. Adventurers will still handle gold coins, after all, past a certain level.
As it stands, in my AD&D 1 game nobody wants to take silver and copper because it’s worthless. When you need 15 GP to buy a long sword and 400 GP for platemail, a pile of 10,000 CP worth 50 GP (1/8th a platemail) is just stupid. You might as well sift out the gold and throw the rest on the floor. (I suspect that’s why in B/X an unguarded treasure hoard always has silver in it – someone came through and looted as much of the good stuff as they could carry). If the coins were worth 10x as much, there would only be 1,000 CP there, and it would weigh 10 lb instead of 1,000 lb, but still buy 1/8th a platemail.
But platemail (and other armor) probably needs to change too. Let’s say your platemail is 45#. If you use 1/10lb coin weight, it’s 450cn, but if you’re on 1/100lb coins it’s 4,500cn.
Iron right now in real life is worth about 1/20th copper’s value. It’s actually 1/26 but there is no way I’m using that in a game. One problem is that copper has industrial uses now that it wouldn’t have in D&D. I’ve heard that copper wasn’t worth much compared to silver until it started being used for electrical and telegraph lines. Does that mean copper in D&D is worth about what iron is worth? Rarer, but softer and so not as useful? Let’s go with that.
So the suit of plate is worth 450 CP in materials, or 4,500 CP, depending on your coin size. I’ll let realism take a swing here and say that coins really are about 1/100lb and platemail really is about 45lb. Based on that, in game the platemail has a material value of 22.5 GP melted down. Using the AD&D coin weight, it’s only 2.25 GP. If you want to preserve modern copper vs. iron values, cut those by 1/20th.
The 1E DMG lists the additional cost for a craftsman working on a piece, under Expert Hirelings, as 10% of the value of the completed piece. For platemail, that’s 40 GP. Let’s say the finished leather pieces, the wear on tools, fuel for the forge, etc. are included in that 40 GP (although it’s not paid when the armorer just works to support soldiers). I think it’s reasonable to assign that 10% if coins weigh 1/100lb but if they only weigh 1/10lb the material in the armor is almost nothing.
This has consequences for PCs immediately. Imagine you smash your way into the Swamp Witch’s hut and after smacking her Giant Asp you find the following loot:
What would you take? My first reaction, from an AD&D 1/10lb coin perspective, is “if we have time to haul it back to town, all of it, on several rowboats, otherwise just the gold”. But what if we give the values and weights in 1/100lb coins?
1,000 CP = 10# and 5 GP
1,000 SP = 10# and 50 GP
100 GP = 1# and 100 GP
Platemail = 45# and 400 GP
Now remember an average-STR PC can carry up to 35# of gear at full movement, and high STR raises this amount, and a party of 6 splitting this up means just 11# each.
If Smaug’s hoard is 1,000,000cn, that’s 10,000lb. It will take 17 mules to carry it but it is possible to transport it. Any normal D&D dragon hoard is movable by a strong man with a sturdy backpack. All but gone are treasure-hauling logistical nightmares.
If you still want that, I suggest putting in fewer coins and more tapestries, paintings, big oak desks, heavy silver mirrors, ebony statues, etc. These things should have a weight of ten times normal coins (back to 1/10lb) but if the players want treasure that’s what they have to deal with. You also get to deal with finding a buyer, haggling, vagaries of the market, “hey that painting is of my ancestor Gutboy Barrelhouse II!” etc. Assmuming you find that fun. If not, make a larger proportion of treasure in coins.
But let’s say you don’t want to change from by-the-book 1e/2e AD&D. You can still get away from the coinage weight problem by including more gems and jewelry and magic items in the game’s treasure. This shrinks the weight of a hoard because gems and jewelry are really light for their value.
I think a lot of problems with flooding of markets in D&D stem from too much coinage. What if the PCs come back to town with a tapestry or magic item worth 1,000 GP and can’t find a buyer with that much money? It’s not wealth, it’s the ready cash that’s the problem. So you trade for 1,000 GP worth of land, or horses, or armor, or whatever. Players would just need to get past not having actual coins. They would hoard coins because they’re easier to carry around and would trade away their captured furniture for new equipment and such. This also solves the “I donate 10,000 GP to my temple” weirdness, changing it to “I donate that nice bed and all those old books and papers to my temple”.