While there is an issue with the name bitcoin implying it can't be divided, I think it also serves as a good way to identify that it's a currency in the same manner a gold coin is currency.
I dare say in time there'll be mbc (milliBitCoins) and ubc (microbitcoins) as time goes by, but for now the term 'bit coin' is about as easy as we'll get to be able to explain this weird thing to the uninitiated

I'm happy with the wallet analogy since it forms a container for your bitcoins. Traditional wallets may contain cards that unlock ATM transactions, so a wallet need not contain actual coins - just the portal to get to them
How heavy is a BitCoin anyway? I guess they're measured in CO2 from energy generation?
