Hello @michael , related to «make them smarter» see my proposals items 1, 6 and 7 here
In general i would not limit «smarter» to SPLs.
Both Radio and Daily mixes has the potential to improve and become «smarter». My thinking here is that «smarter» goes beyond pure rules and logic like more boolean instructions being added to Focus , which is also welcomed.
Though i am not hugely impressed by the use of AI alone to create PLs/Radio (Plex , Soundiiz).
I believe that a combination of user input (Focus) and AI/Sonic analyzis would be the best solution where the user input has priority over «the machine» 
Extending Focus to include streaming sources would be a good starting point , especially for discovery.
This could be implemented and released as smaller increments as long as direction is defined and the underlying architecture supports this .