Actually the Steem blockchain is very flexible. See this excerpt from one post of @dantheman:
What if it were possible to build custom applications on top of Steem? If you think Steem is only here to serve the niche of social media, then I consider this you wakeup call. The Steem blockchain is already capable of supporting every kind of blockchain application you can conceive. Best of all, you don’t need anyone’s permission to start building your app today!
Think of your favorite blockchain application. Is it Auger with is prediction markets? Is it The DAO? Is it general purpose smart contracts? Is it Dash with its privacy features? Is it decentralized voting or DNS? All of these things are possible on Steem today and you don’t need Steemit’s permission to do it.
RE: EOS vs. Steem