I think offering (a) badge(s) for users who choose to make their answer a Community Wiki answer would be a nice way of encouraging/rewarding those who dare to do so, even when neglecting a few/many potential points. Because we all care about our site reputation. I post this as a feature request. Also to hear you opinions on this.
We've been slowly backing away from using Community Wiki in most situations. That doesn't mean the badge is a bad idea. Rather, we'd want to find a way to make a badge that encourages the rather nuanced behavior we want to endorse. And that's not going to be easy. If you have some ideas about how to make a badge that does something other than cause people to randomly set some of their answers Community Wiki, please let me know.