I'm wondering if the Steemit community ourselves could hack this a little with a cultural practice:

If the author were to leave a comment on the post at the end of the same day...something along the lines of:

"If you found this blog post valuable and would like to support my work after the 7-day window. Please upvote this comment. I appreciate your support!"

I realize this isn't a perfect hack. There would need to be a new author comment every 7 days to keep extending the window, but if we as a community accepted this practice by actually using it, perhaps it would signal the value of some sort of extension by the developers.

It would be cool if a post were able to hit a trending benchmark that would make it eligible for a second round of voting.