Let me be very clear - I have very low expectations from SMTs, particularly the spec proposed by Steemit. I haven't followed development so I don't know how it has evolved. The Steem Engine and tribes stuff is a tangential prototype (and is arguably more sophisticated already) that suggests what we already know - it's very, very unlikely it'll have any significant positive impact. The social media space is mature and saturated, even if one had deep pockets and sought to revolutionize the market, there's basically no rational reason for building it atop Steem.
I misused "SMT" to mean the current spec, as you correctly point out. To clarify what I said above, I want admins and moderators to have the tools required to configure their own communities and tokenisation however they want. I'm well aware this is not what "SMT" means currently and will take years to develop, as I made clear in the OP. I absolutely agree these should be fluid smart contracts rather than hardcoding everything to the blockchain, which has no practical value beyond some misguided idealism.
None of this will make Steem a "Facebook killer" - that's simply delusional. But we are at a dead end with the current paradigm, in my opinion, and must try something different.