Saw Episode 5. They have committed sins I strongly dislike, and that occasionally plague SW stuff under Disney.
A couple episodes ago, Obi-Wan sees Quinlan Vos' name carved in the safehouse wall. Quinlan Vos is a character chiefly fleshed out in the comics, and is Obi-Wan's oldest friend. At first it seemed like a toss-in Easter Egg, with fantastic acting from Ewan who shows a mix of relief, affection, and nostalgia upon seeing the name; a very cool moment for people who'd catch it. With Ep 5 though, it's clear that wasn't just an Easter Egg. It's foreshadowing. Reva's arc mirrors Quinlan's, and does so closely enough that I'm concerned she's gonna become a take on a Quinlan-like character, when a dude like that could easily warrant his own pretty f***ing awesome show. I have thoughts about what this means for her character and the chance that her not fitting as a villain making more sense and being deliberate rather than bad acting (doubt), but mostly I'm annoyed that they'd handle a reference that important and vital to understanding what they're doing with a character like that. Maybe what, 2% at most of people have read the Quinlan comics where that reference and the comparison to Reva are possible? Good for the writers doing their reading and flexing their knowledge, but once again Star Wars forgets to be accessible for the vast majority of viewers, and leaves people rightly more baffled than they need be.
In comics and other media going back ages, it's made very clear that that the Sith and darksiders feed on fear, anger, and hate. So they often string things out and play with victims to max out those feelings for their own benefit. Palpatine rejoices on some level at the Rebellion because the conflict and its feelings feed him; the Death Star and the fear it is meant to evoke will replace that. Thus why a darksider like Reva would use the artillery to slowly pound at the door instead of cutting in immediately, as it's shown she can do. Here's the thing though, despite this being a canon thing, Lucas and everyone since just takes for granted that people know this and it's never really explicitly explained in the main movies and big shows. It's never properly communicated, and so it makes for situations that come off as nonsensical and pointless. It's a major motivator that is kept in the dark unless you look for it. This is bad writing, and it's an error the franchise makes repeatedly. The people making things fail to realize viewers don't have the same knowledge as they do, and don't pass it on. Anyone who complains about the seeming plot holes created is justified in doing so. You shouldn't have to do research to understand what you're seeing.
Similarly, Vader has maximum scorn for Inquisitors. He holds them in hilariously low esteem. They're knockoff toys he doesn't want, but Papa Palpy makes him play with and use so he can focus on bigger tasks. The notion that Vader wouldn't deem Reva as being even worth killing, as being beneath trash to be cast off, is something he'd have drilled into them and would have been affirming; it's another kind of torment in a long string of tormenting those people. Hell, the Grand Inquisitor wants to kill him and take his job and Vader doesn't remotely give a shit because he doesn't recognize any of them as being remotely a threat; he is more worried about Jedi than them, and loves letting them know. This is known and easily inferred if you've read that shit. If you haven't though, Vader leaving her alive makes zero sense and isn't justifiable.
Someone needs to sit down with SW writers and remind them that if something isn't explicitly stated in any of the movies, it should be assumed nobody knows them.