Plunderer was an anime with potential that unfortunately trips over its own feet trying to reach it. The pacing and story are kind of all over the place, and a big reveal leaves less of an impact because of it. Spoilers Ahead

Plot (5/10):
So from the beginning I had a hard time understanding what the actual point of the story was. The first few episodes introduce the main character, Licht as the (obvious) Ace Hina was looking for, however he is currently moonlighting as a giant pervert. For the first 1/3rd of the show (until the episode aptly titled "Plunderer"), you are not only drip fed information about the rather non-existent plot, but also subjected to a non-zero amount of filler. After episode 9, the story begins to take off, with what seems to be the main arc of the show, a huge "flashback". Honestly, I don't have too many big complaints about the pacing here, but it's after the flashback arc ends that I think Plunderer starts to struggle again. Episodes 18 (the end of the Flashback arc) and 19 have such a gigantic tone shift that it's legitimately jarring. They take all this time to develop the plot, drop such serious developments and information just to lead into an entire "filler" episode only about boobs and booze. This is something I'll discuss more later, but the show was filled with weird tone shifts like this. It felt like it was trying to mix ecchi and action/thriller, but the switches between the two don't work out.

In general I also felt like there were a lot of plot holes that aren't really explained at any point. Here's a couple I felt were left unanswered:

Why is Schmerman the only one shown with native ballot powers? They mention some humans are on the same wavelength and were granted these powers, but what happened to the rest of them?

Why were they able to vote to create a floating continent, but not change the barren nature of the earth? They specifically refer to it as bending the laws of nature, but I guess there are limits?

Why do Aces not age? They went out of their way to explain Licht went into a coma and after, stopped aging, but what about the rest of them? Why do some of them age to a certain point, then stop?

Towards the end, not only does Licht "die" fighting Doan, but for some reason even though the SSU was commanded to capture Licht and bring him back, they see Hina and crew digging for his body, and ONLY capture them but not Licht's "dead" body? Then as Lynn is about to draw her last breath, the townsfolk show up out of thin air? Then Licht breaks out of the black hole Doan sucked him into?

Honestly, the plot here was just a bit too flimsy and had a bit too many holes.

World/Setting (8/10):
I would say this score is entirely dependent on making it to episode 18. Before this, the world is just a semi-generic fantasy land, even if you don't see all that much of it due to the flashback arc. Alcia being revealed as || a floating continent utopia, where the "Abyss" is earth from which they steal resources from|| was something I didn't expect, and pretty well executed. It even explains why the helicopter in episode 8-9 shows up.

Characters (7/10):
I felt like the characters in this show were alright. I think Licht's transformation from Rihito to Licht also made sense, given the atrocities he dealt with in the war. I will say, I did not like the almost 180 in Hina's personality after they come back to the present, where suddenly she's this sexual being trying to have Licht's babies. I also think Jail was a tad bit too inflexible, in the way that his convictions were ALWAYS brought up. I think that was a writing issue, because it didn't need to be stated literally when his actions speak for themselves. The "reveal" of Pele's true nature was interesting, but didn't go anywhere since it happened at the end of the series.

Visuals (7/10):
Nothing to write home about here, generally ok, and didn't do anything too crazy. Art style has been done before, and It felt like the chibi, cutesy, visualization of characters in some episodes was a way to save on animation costs, but who knows.

Audio (7/10):
Soundtrack fit the show and was generally consistent throughout, but didn't fill me with any strong emotions. OP and ED were serviceable but not memorable.

Enjoyment (5/10):
Ecchi. I have never had a problem with his genre. Whether that be a straight up ecchi comedy like Prison School, something a bit more serious in tone like Harem in the Labyrinth of Another World, or something integral to the plot like Chained Soldier (not enough ecchi imo) or High School of the Dead. But my god. The constant sexual harassment in the show was undeniably the most off putting thing I've seen in a long time. From the beginning, Licht is billed as a pervert. This is not a problem within itself, but the almost immediate and constant joke of "spread your legs" and forcing Hina's legs open was too much. It took me away from the story and just made me enjoy the show less and less. As I mentioned earlier, the switch between episodes 18 and 19 felt like a visualization of everything that was wrong with this show throughout. At one point, Pele is having a heart-to-heart with Lynn, the girl he clearly likes, and in the middle of it says "stop acting like that, you're making me horny". ????? Was this supposed to be funny?? I even at the end, when Pele is "checking Lynn's wounds" the forced leg spreading and innuendos don't stop, and it just feels extremely forced. And again, with Hina's new desire to make babies, it makes me think back on her first interactions with Licht who by his own admission, is essentially her uncle. Sure we can excuse the 300 year age gap since he's still "technically" a young adult, but that is his adoptive brothers daughter who's legs he's trying to spread... Oreimo was one thing, and this is another. This is yet another example of the forced ecchi dynamic as well as the age issue that isn't explained, because how exactly did Hina's mother live for ~300 years before having Hina, when Tokikaze was clearly killed ~300 or so years ago?? Stuff like this really detracted from my ability to maintain my suspension of disbelief and ruined a lot of this show for me.