DJs are the obvious place to start on compulsory licensing given that such already exists for covers of songs. Introducing standardized terms for sampling would be a small step in the right direction (something you seem to be advocating when you're talking about terms) in an industry that already understands it and has been there in the past (e.g. Paul's Boutique would be impossible to make nowadays). This helps build up towards e.g. standard licensing terms for reuse of characters (something that big content has a lot to gain from, but would likely be too afraid of at the moment).