Pleasantly surprised by this episode and Season 4 in general.
Red Daughter is a great character and is a bit of a confirmation of what I've always suspected and pointed out - Kara Danvers, for better or for worse, is very much a product of her environment. She is undisciplined, she keeps a boring daytime job in hope of seeming normal (which she only does every now and then with her cover slipping often at worst moments possible), she's a bit arrogant and relies on confirmation bias, often admitting that she was wrong when it's late. Interestingly enough, Snowbird lacks most of these flaws, because she was mentored by a genius polymath with certain disdain and disappointment in people and it's interesting that Lex only narrowly escapes being outed with his ulterior motives by critical thinking he was able to mentor in Red himself. In other words, this season's battle of two Karas is not just two superstrong individuals wrecking the city because Earth-38 is free real estate: it's clashing of two different personalities and thinking styles, both of which are not bad at all, but both of which can be misguided. Of course, it must be noted that whatever the nature of Red is, even a clone of someone can't have the same exact personality, but the difference in two Kara's seems very much like a point of how education shapes people but something entirely else defines what they are and whether they will use that for good or bad and that something might actually be worth considering. I'd say that Otis Graves showing surprising soft spot and Lex Luthor doing a bit of the same in the episode actually strengthens the point, as well: both are outright villains, but that doesn't mean that they're that different from humanity even if they are exceptional at what they do.
Triumvirate of villains showed some hidden depths both in terms of actors being great and writers giving all of them some really great pieces of dialogue, interaction, exposition and more. Lex Luthor is rather amazing, being on one side genius enough to devise some of the most complicated plans and actually execute them and on the other side downright psychotic and only able to read human emotions to a point, not even being able to notice that Otis Graves is a bit more humane. Speaking of Otis: episode actually shows a thing or two on why Luthor keeps him and probably even prefers him to his sister, Mercy (who was Lex's girlfriend at one point in this universe): Graves is not only quite loyal, he knows limits of his incompetence and is surprisingly adept at building network.
As for Eve Teschmacher... I guess there's more to her given the name of the next episode, but it's clear that she also knows her way around Lex's weakness and might see it as too much of a flaw in his plan. It's a great and interesting moment that her overall personality is not that different from what we've seen: if someone is going undercover it is a good idea to not be faking if you only can do that to a point, so that's what she did: marginal adjustments to her own personality.
Finally, Russian in this episode is surprisingly good: a few people have accents, but Jon Cryer and Melissa Benoist seem to have great ear for languages, especially given that preparation time was probably very much limited. Aside from a few flubs here and there, Russian writing actually add up, as well.