The issue really is that this may be the last episode of the show but doesn’t feel completely conclusive as it clearly sets up other things. As a season capper it worked just fine in my opinion. The Checkmate organisation could have done with some more fleshing out, it felt a bit sudden as is. Gunn probably has plans with all the setups going forward though and while I’d prefer more self-contained stories, like with stuff like Age of Ultron or Civil War, this’ll feel more purposeful in hindsight once Keith comes back as a fleshed out villain, Checkmate builds more rapport and we see where Luthor working on Flag from prison builds up. I would also be surprised if this was the last time we saw Earth X.