1. Witness rewards are paid as STEEM at a rate that covers costs. (Kill the payout in SP).
2. Kill the Power Down contract of two years. Change it to 4 power down payments over four weeks. Also if powering down - then no voting power for that stake.

1I am not sure why you would want to change anything with the witness rewards. This reward is included in the approx 10% yearly inflation, it is not the cause of the price going down.
2 Why would you want to shorten lock time period while keeping the same inflation rate, this is going to be even worse.

. Those in SP get the opportunity to earn from accurate CURATION.

This is already how the system works

AND 5%.

5% of what? new created coins? why would you want to give SP holder an extra incentives? The system was designed to reward SP holder with curation rewards, the incentive is there already.