Next to rule on: SEO and Ads
Huge fines for PageRank manipulation are necessary. Those include link selling, buying, or maintenance of satellite sites for fake back links.
Paid ads should be made clearly distinguishable from other content with additional reputation metrics visible to the users. The metrics should include destination domain age, full contact information of the advertiser, quality of such contact information (specific vs 3rd party), a malware and phishing summary from multiple scanners (like Virustotal).
Contact information of advertisers must be verified by sending physical cards to those addresses. Which means no more virtual contacts. And if redirect funnels are used, for example 3rd party postal redirect services, those should be marked as such based on aggregated signals when multiple advertisers use a single postal address.