The Luthor AU world is very interesting! I really thought that the show would've benefited from a two parter for Luthor so we could see more. That Oliver Queen could make for a good case study, because, as you said, we don't know much. He seemed to want to do good but didn't know how to go about it- also looked to be very lonely outside of Lois. There is room to play around there and you should totally go for it. Good luck if you do!