Referal links are - in principle - not issues at all, when they are good ones. The malicious ones, they need to be removed from the platform. I agree with your proposal. Currently, Steemit does not have a real content cleaning system, other than for plagiarism. I think an automatic services, or services shall be created to take out malicious referrals, or even better, malicious URLs (referrals are nothing more than a URL and can be embedded behind words, images and other content.