Indeed steemit have potential issues on their rewarding system such as centralization of their token mechanism but steemit is still the leader & whenever we think about blockchain based social media platform then the first name which appear is the steemit. There are so many other alternative to steemit in the market with same or similar aim such as Qbao, akash, synereo, U network etc. Out of this U network looks very closer to steemit & you can know more about U network here https://u.network/