Just wanted to mention one more method to get more out of your Steemit assets, which is arbitrage.
If you monitor the prices of STEEM and Steem Dollars across external exchanges (eg: Poloniex), you will find price differences between the internal rate found here on the website, and external exchange rates.
So as I am typing this, if I were to deposit 1 Bitcoin directly to Steemit, I would receive 178 STEEM. If i were to exchange that 1 Bitcoin on poloniex for STEEM, i would receive 196 STEEM. A difference of 10%
Fundamentally what this means is that because the internal market does not have any direct cash out function, the external exchanges are where people are buying and selling Steem assets for bitcoin or other currencies.
The price differences found between the two exchanges is where the opportunity comes in to receive more for your bitcoin or your existing Steem assets!
Certainly, though this is not really relevant to Steemit itself. All of this happens at the exchanges outside of Steemit.