Actually this is an interesting and reasonable idea of dantheman! I think at the moment the term Steem Dollar has the advantage to win people who are new to the cryptomarket/cryptocurrencies , so it is better not changed.
But we have this (to my mind useless) Savings column, which could be substituted by a Steem Silver (participation). So we interconnect the value of this part of fortune to silver. As a result everybody on the steemit network can decide how he wants to story his Steem (in Steem Power, Steem Dollar or Steem Silver).

I think many people on Steemit anyway have other currencies so the fast tradeable steem dollar gives them enough to survive...