I am not sure, whether you know, that PoW will be removed from Steem in next hardfork:
https://github.com/steemit/steem/releases/tag/v0.17.0rc2
PoW is being removed.
PoW has been broken for a long time. Very few people pay attention to it. It is dominated by the same few people and is providing very little value to Steem. Instead of investing even more time fixing it, we have decided to remove it entirely.
Oh, I didn't know that. Thanks for letting me know. I just joined steem 2 days back. ;)