Bounty questions should get bumped periodically.
This is a screenshot from the Stack Overflow "Featured" Tab, highlighting the view count of bounty questions ending tomorrow:
Considering that these questions have been on the featured tab for 6 days, their view count is not impressive1. Since offering a bounty is the proper way to attract attention to an unanswered question, I suspect that at the moment they are not being fully exposed to the active experts in the respective fields.
I was thinking that since the Community User "pokes unanswered questions so they get some attention" (as stated in its profile), I wonder if it would be a good idea to also make it poke bounty questions periodically, relative to the time the bounty was offered (in order not to bump them all at the same time). Especially since bounty questions are by definition "unanswered", and require extra attention.
It doesn't have to be too frequent. I imagine something like bumping bounty questions every 6 hours for the first 2 days, then maybe a bump every 12 hours for the remaining days. An automatic bumping event could be skipped if the question got already bumped by someone posting an answer, or making an edit.
1 There is also a post on meta from last January that raised this issue.