I think it would be an extremely powerful feature to have the ability to subscribe to ad blocking lists. Examples would be the Easy List forums (https://forums.lanik.us/) or those provided by Malwaredomains. This could fit beautifully into the web interface tab with a simple check/uncheck the subscriptions, with the option to type in your own subscription
I didn't really understand if this new function also lets you add the easylist URLs, since that data isn't in standard host format. Would be fantastic if it that was possible though!
No, it is just an interface for the already existing possibility to add (compatible) lists by adding them to the lists file. There is no additional parsing/formatting done by this code.