On the topic of coins, you could have many different types worth different ammounts. You could also add weight to them. Then you have the problem that I heard one DM forced onto his players.
He made all treasure drops in Copper Pieces. The players had to decide whether to take the items or the treasure. How much is it going to upset players when they can't pick up coins because they're in such small denominations, yet weigh so much. I think they'd be better off leaving just gold coins, but adding weight to them. How much do you carry and how much do you stash? Gems would also have a better meaning now as they are light weigh sources of money. How good a deal are you getting on your gems?
