Given that Supergirl more or less did it's own thing for the last season and created a huge problem for Superman's family down the line with the ending, should S&L just take place in it's own universe? It's more down to Earth tone seems a bit out of place in the rest of the Arrow-verse. Supergirl just picked up where it left off on Earth 38. Complete with the pre-Crisis fortress and blue heat vision. The ending of COIE doesn't rule this possibility out. Superman would still exist in the Earth Prime. He just didn't show up in the Supergirl show. You can still have Flash show up on S&L, it would just be that world's Flash. S&L doesn't acknowledge Kara, or even the rest of the Arrow-verse outside or maybe Diggle. I think that S&L works best as it's own universe. And by placing it in it's own universe, you side step the ending of Supergirl. And the more silly shows, like LOT. What do you think?