Well, this already exists, really..
the community user bumps (n) unanswered posts per hour to the front page. Unanswered is defined as no answers with upvotes.
edits to your question bump the question to the front page.
new answers bump the question to the front page.
edits to answers bump the question to the front page.
after 2 days you can issue a rep bounty on a question which keeps it on the "Featured" tab on the front page for 7 days
The general philosophy is here:
How do I get attention for one of my own questions without a good answer?How do I get attention for one of my own questions without a good answer?