You should really look into EOS. I was heavy into Cardano and Ethereum but since reading up on EOS I feel like it might have an even brighter future. The developer of Steem learned a lot of production lessons that he applied in his new general purpose platform. Eventually something like Steem will also be built on top of EOS, or at least it makes it possible.
As a developer I realized that the approach of having to pay for each and every transaction/instruction on the blockchain makes it very hard to scale enough to disrupt some of the big tech businesses of today. EOS’ approach of giving you a certain rate limit of free transactions for every user seems like a very elegant middleground.
RE: I'm ALL in on STEEM - Why Steemit will have Massive Growth in 2018