I think all these polls should be tossed out and replaced with new ones. The problem is that we don't have enough options. We only have 5 options when really, we should have 10 options (i.e., 10 stars).
If I want to vote in between, I cannot. Not all these options fit. A middle option would fit better in a lot of cases. So instead of 5 stars, let's move to 10 stars. It's easy enough to create new polls with 10 stars instead of 5. Granted, it would mean starting over, but it would also mean a lot more accurate results.
What could be done is new threads created and then the moderators can merge the old thread in the new thread without the original first post and then delete the original threads. That would work very well and once done, we'd be all set.
Why stop at 10? Let's go with 1000. Then we can see what people really think...
Seriously, I think Thrawn has the killer argument for leaving it as is, if it's good enough for Amazon and Goodreads there's no reason I've heard that 5 doesn't work. And no reason for Sho to do all the work involved in updating his scripts and no reason for the mods to spend time creating new polls and combining the old ones.
We're rating tie-in books, not putting a man on Mars. 5 stars seems to be doing the trick.