Yes, I think something like that would be absolutely needed if we want Musing to have a real user base. Right now it's filled up with so many spammers who write a question, then copy-paste an answer to their own questions (and get $0.5 upvotes each time they do it!), and I believe a point system or something like that could be useful in preventing or limiting this type of behavior.
And for us real users, having a point system would be a nice thing as well, since we would be able to "show off" our efforts in our profiles.
I agree, musing should have some user reputations for two reasons, to avoid spam, and to motivate real quality content creators