Blocking search engines without effective safesearch like Google and Bing have

Hello.  Would you guys be willing to block all search engines that do not employ an effective safesearch like Google and Bing use?  I have found dozens of little known search engines that either do not have forced safesearch, or have safesearch that is easy to circumvent.

Also, any progress on using keywords either from the URL or from the home page of a website to add to the blacklist?

Thank you!