For what it's worth, I'm not feeling the loss. This episode was excellent.
Carmen started a bit too sueish for someone outside of law school, but this episode brought her back to earth and had her losing control of the situation as well Liz getting called in on her case, which had some interesting grey morality. Hopefully she isn't another one season character.
Diane stopped doing drugs or whatever she was doing in S3-4 and the show brought her back to more realistic cases, dealing with her marriage and navigating the politics of it. Also she has some pretty fun interactions with Julius.
The only thing I'm not liking is the fake courtroom storyline and Marissa becoming a lawyer (Which feels like it exists just for that story), it feels like the usual TGF doing experimental stuff.
Season 4 felt like it jumped the shark with Epstein and the Memo 618 stuff, I wonder if they toned it down because of it.