First of all i will go through what is crypto currencies?
These are Digital float, Block and numbers, Which have different prices. For example rate of one Steem is at $ 0.18 , which is equal to 29.94 PKR. That's is the crypto.

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It won't stop here, there 6,955 digital currencies. Steem is one of them. BTC Is the leading currencies.

If can make change in this world, That changes are below🔰🔰

1. In this block chain i change the reward division system and take back to 25 % curation reward and 75 % author reward.

2. I add more option in reward taking system as you mention in your post. 100 % SBD. And also listed many other coins that author want to take reward on the place of steem.

3. And also reduced the time of power down from month to a week. But steemit has done great system then hive.

4. Payment system, There should i change payment system. Everyone can change their steem direct into their local currencies like PkR. For this special site or app is designed.

5. Block the supplies of steem for trading or make forbidden the trading of steem on big value. by blocking the steem supplies for trading it can huge push steem to upward in price.

Note these all are my opinion so don't get any wrong idea..