CPU Mining is not viable anymore. As you know, Rabbit and Supercomputing have nearly taken over the mining queue. Hardly anyone else besides those two dominate the queue. And, as a result, I winded down my miners, it seems the developer will not intervene on the current situation. and it's time for us weaklings to move on.
https://steemit.com/steem/@anonimau5/miner-witness-queue-weirdness
Here is 
This is just how hashpower is divided. They are not milking anything, they are bidding the most computational power for the steem. Letting more people know about the mining opportunity would likely increase the difficulty and variance. All told two people with 47% of the hash power isn't that bad.
I personally wouldn't be offended if one person had 99% of the hash power. The security provided comes from the computation work done, not the variety of people.
This is my previous post about the current situation.
https://steemit.com/steemit/@alphabeta/only-the-strong-will-survive
The following posts are from other miners about their feeling.
https://steemit.com/steem/@bola/steem-cpu-mining-i-surrender
https://steemit.com/steem/@arcange/the-end-of-steem-cpu-mining
https://steemit.com/stats/@arcange/the-end-of-steem-cpu-mining-update
https://steemit.com/steem/@cryptohead/steem-mining-queue-dominated-by-the-rabbit-servers
https://steemit.com/steem/@steevc/maybe-mining-is-not-for-me