RWBY season 3 and onward
The show should have never promised to be a huge, shounen adventure series.
The appeal of the first two seasons was that it was fun, slice of life shenagains with wacky comedy that just happened to be set in a cool urban fantasy setting. People weren't judging the story for character arcs, or the plot progression, or trying to figure out what the relics were, or whatever. It was a fun fluffy junk food show and was good at it.
- Then season 3 happened, and it promised the world, and it couldn't live up to the expectations it had set for itself. It promised deep character arcs... but there were too many characters to properly explore for a seasonal 12 episode series in which episodes are 22 minutes long. Even when characters were thrown out, like Oobleck, Port, Glynda, Ironwood, Penny's Creators, Tai Yang, Neptune, the other hunter teams, and so on... there were STILL too many characters they couldn't juggle properly.
- The worldbuilding was irrelevant fluff in season 1 and 2, but then in season 3 it became critical to the satisfaction of the story, but the worldbuilding was awfully presented before. It was never integrated itno the show, so much that the team had to create an entire separate series outside the main show to explain what was going on (and even the main show kept retconning the world). We know next to nothing about each kingdom. We didn't even know that Vale wasn't actually just a city state until the season 4 WoR, and that is egregious given that the first 3 season were set there!
- Since Monty's death, the show hadn't been as enjoyable to watch per episode. In season 3, all of the fun of the first two seasons was removed, and the shounen adventure that was filled in to replace it was mediocre. The adventure story moves at a snail's pace. They spent an ENTIRE SEASON just sitting around inside a house doing nothing while the plot happened offscreen. When freaking One Piece has more plot progression in 36 episodes vs RWBY's 72 episodes at the end of season 6, you know you have a critical storytelling failure.
I have many more problems with what happened to the show after season 2, but I digress. Season 6 was the last straw and I really should have quit earlier.
Aldnoah Zero second cour
Where the second cour dropped the ball was in it's scope: whereas the first was a small scale story on the ground about a few characters with (relatively) small stakes, the story felt powerful and the conseqences dire. The second season then devolves into having the same small number of characters effectively deciding the fate of the world in 12 episodes whilst fighting in outer space. (The outer space battleground isn't inherently bad, but you see my point). This leads to the war feeling unrealistic given the grounded nature of the first season. Not to mention, the first episode of season 2 literally opens with a beach scene, completely negating the dire tone of the first. The immense sacrifices made in the first season are completely retconed, with all parties involved being reset. Saazbaum is simply evacuated to another castle with the same standing within the knights and the same amount of forces as before (and a repaired Discouria too), the Deucalion remains undamaged and operable despite having crashed at hundreds of miles per hour. Rather than having sacrificed hundreds of good troops and quality equipment to push back a single Versian castle (out of 37/38/39/ don't remember exactly how many), the Terran protagonists effectively get a free victory which not only pushes back the Versians, but they have somehow attained the upper hand in the fighting months later. The entire setup of the second season undermines the achievements of the first. This BEFORE we even get to the new season 2 content... I could make an entire post about that, but I digress.
What I would have done would be to continue the grounded, small scale war story. The first season was a struggle against a couple of counts and resulted in the destruction of a single landing castle (out of 37/38/39/whatever, there's dozens of them). The second season could have followed a campaign to liberate a country or peninsula.
Gundam 00
The first 14 episodes were great when it was about four guys with the entire world coming after them. It was a high stakes thriller and I watched every episode eager to find out how the various superpowers were going to try to capture the Gundams and how the heroes would escape. Then episode 15 introduced the three Gundam pilot antagonists and it lost all the stakes as they bailed out the heroes and the nations became irrelevant as the story turned into good hero gundams vs evil gundams and their alien worshipping cult.
Gundam Iron-Blooded Orphan season 2 ending
IBO S2 ending
Rustal Elion needed more set up so that his triumph didn't feel sadistic. He needed some focus to convince the audience that his victory would still be a net positive for the world, and we needed to see more of the state of the world after his victory to cement that feeling. But as it stands now, it feels like Rustal paid lip service to changing Gallarhorn, but nothing actually changed and the good guys died for nothing.