Aye, agree - no new buyers, unless you want to sell your shares? I guess some simple exchange could be made but I'm not such a pro dev and don't have so much time to make it fast and easy to use :)
As for SMT - very interesting idea but currently I have no idea how I could issue SMTs, track their number for shareholders and finally allow shareholders to trade them :) time will tell, maybe I will be able to dig into this but it requires time - I wish I had more :)
SMT are not even fully released yet :)
And for simple sell you can be the exchange but you charge a fee for an exchange bc it not easy.
For smt token there will be an easy token issuer, token tracker, and it will allow smt asset to be traded in an internal exige saw it on some post.
https://smt.steem.io/