In adition add the packages "my bookmarks" in your SMF.
It would add the option to bookmark threads you visit regulary.
And it adds a "My Bookmarks" next to "My Messages".
A Admin could install it over the forum CP panel,
pulling the bookmark mod from the SMF packages stream inside SMF CP.
Or get it form the SMF website.
I think it would be a great addon for the site and the community.