A significant portion of spam contains commonly spammed links and product names, such as:
Almost any post containing these is spam, especially from a 1 rep user. Additionally, blocking curse words or insults could help block offensive posts. Commonly spammed product names and links should be blacklisted. Why wait for users to flag them or moderators to delete them, if you can add a content-based filter, that prevents many of such posts from being submitted in the first place?
I propose that a set of blacklisted URLs and keywords be added to the new user restrictions, so that many spammers (the vast majority of which are unregistered or 1 rep users) will be denied from submitting their post. It might happen that someone may have a valid question that happens to be about or involve one of the blacklisted words, so that's why it should be a new user restriction.