The amount of reward should adjust according to how far off the dollar is from the target.
Let the witnesses decide. Add Parameters.
reward_dollar_only_price
Set this value to a value of a SBD in USD. When the marketmeetsorexceeds this value rewards should be 100% SBD and no liquid steem.
reward_steem_only_price
Set this value to a value of a SBD in USD. When the market fails to meet this value, rewards should be 100% liquid steem and no dollars.
At 1 SBD = 1 USD. Allow for 50/50 rewards. In other places not mentioned do a linear interprolation:
If the reward_dollars_only_price say 3 USD / SBD, and the price is 2 USD/ SBD; then the ratio should be 50/(3-1)*(2-1)+50% SBD = 75% SBD. That reward should be 75%/25% STEEM.
Interest on SBD only makes the SBD weaker in the long term. This solution also helps the SBD dollar as well.
It is a good alternative proposal. The main concerns are that it adds a lot of complexity, which is confusing to the user, and if there is a very large demand for SBD it could take months for the production to catch up with demand.