Some topics only last until the poll ends, and them people lock them. I was thinking, maybe there could be a command that automatically locks the topic when the poll ends, to stop discussion about it?

I like the idea idea but unfortunately there's no way for me to integrate this feature unless we can find a phpBB add-on for it (which I can't seem to find) or I code it myself (which I don't know how to do)

You'll have to get a moderator to do it instead