Despite how much I love Superman and Lois, I don't think this show needs to acknowledge it when we're so close to the end. Have Kara show up on that show, but let this show keep on with its own characters so we can get fully realized endings for them. I think Lena and Nia have a great relationship now. I don't know what Andrea's problem is, but I do enjoy seeing the Kara Danvers side of Supergirl's life and how she is going to live that part of her life.
Leave it to Supergirl to clumsily deal with real world problems. I get why they wanted to bring up environmental issues, but comparing Earth to Krypton and having a simple solution like using alien technology wasn't the best thing.