There are reasons to issue them, but creating an asset is not enough to make it useful. Look at bitBTC. This asset makes a perfect sense, but liquidity ...
The free market has spoken... people have indicated that they prefer an IOU for the real thing (OPEN.BTC or GDEX.BTC) rather than a derivative (bitBTC). I view the cryptocurrency Smart Coins as effectively useless at this point... (other than for a small percentage of the userbase that wants to margin trade with them or stay in a completely decentralized and autonomous environment).
But I think cryptocurrency Smart Coins (bitBTC, bitLTC, etc.) may be different than equities, index funds, or commodities. Due to regulatory issues, there is no easy way for someone to setup IOUs for index funds or equities. Also due to custodial/regulatory issues, there is no way to set up IOUs for commodities either.
I think it can be a good for Bitshares marketing to create a few Index Fund Smart Coins. I think the options should represent a decently diversified portfolio. Something like:
VTSMX -
Vanguard Total Stock Market Index Fund Investor SharesVBMFX -
Vanguard Total Bond Market Index Fund Investor SharesVFINX -
Vanguard 500 Index Fund Investor SharesPlenty of price feeds available for all three of those. They would represent ownership in the S&P 500 (VFINX), Bonds (VBMFX), and also the Stock Market as a whole (VTSMX).
I think this would be really good for marketing and bring more users into Bitshares. No other DEX can say they have such derivatives. Smart Coins are Bitshares' killer feature, but they need to be leveraged properly.