I don't think you necessarily need a separate blockchain in conjunction in parallel with Steem while you wait for SMT. With the recent announcement, I am currently working under the assumption that SMTs will show up eventually. I guess we'll just have to wait until January to figure out if SMTs are just empty promises.

Assuming SMTs are coming, then a simple database level tracking of each Steemit's users tokens can work. Obviously, the trust will have to be there since we'll have a lot less visibility into what is happening behind the scenes of these tokens or what will happen upon SMT conversion. A couple of examples of systems already using this are Actifit.io and Partiko. Both have an internal token tracking system without an attached blockchain. Both tokens don't directly have value, but provide some type of benefit to users. Actifit's "tokens" seem to be factored into individual votes while Partiko's can be spent to get upvotes on a post. I feel investing in separate block chains at this point would be a poor choice for the limited time. If SMTs get put off indefinitely, then the whole block chain is probably in trouble.

I know it's probably not the most exciting solution, but the intermediate step of tracking tokens and waiting for SMT to come online seems like the safest choice.