Arc Fatigue: The game against Inashiro Tech is several volumes long. It's made even worse when after all the tension build-up, they lose cuz they blew the save. It's not as bad in the anime, lasting more or less ten episodes; which is only about twice as long as the other games, which average around 4-6 episodes. You still get the heartbreak when Seido loses, but it's still nowhere near as long and upsetting as in the manga.
The story repeats in Act II, with a total of 40 manga chapters from beginning to end, and the game was pretty low on runs. This time at least Seidou wins, though, and most readers agree that the 9th inning was a great end to the match.
Base-Breaking Character: Furuya. He's either an awesome and well-developed character and a much better lead than Sawamura or a boring and overpowered Spotlight-Stealing Squad. There is very little in-between. This is more of a Western fandom issue, though. In the official popularity poll he came in at a smashing fifth place.
Bishōnen Jump Syndrome: The character design certainly evokes this, especially compared to the other sports anime that aired in the same season, Yowamushi Pedal. However, in comparison in other sports animes, it isn't much.
You'd be pressed to find someone who doesn't like Chris Yuu Takigawa. A good portion of the fandom calls him Chris-senpai not just because that's how Eijun calls Chris, but simply out of respect for him.
While all of the third-years are quite popular, RyousukeKominato and TetsuyaYuki are particularly well-liked.
The Yakushi team also has a respectable amount of fans, especially Raichi and Sanada.
Launcher of a Thousand Ships: Eijun, Eijun, Eijun; there's Eijun x Chris, Eijun x Furuya, Eijun x Miyuki, Eijun x Haruichi, Eijun x Wakana, Eijun x Haruno, and the list goes on.
Haruichi as well; Haruichi x Eijun, Haruichi x Furuya, Haruichi x Ryousuke, and the list goes on, it also doesn't help Haruichi that he's a Dude Looks Like a Lady.
Miyuki isn't far from this as well. There's Miyuki x Eijun, Miyuki x Chris, Miyuki x Furuya, Miyuki x Narumiya, Miyuki x Kuramochi and Miyuki x Norifumi, and those are the popular ones.
One True Threesome: Eijun, Furuya, and Haruichi; extra points since whenever Haruichi compliments one of the them, the other gets jealous and fuels their rivalry.
Rooting for the Empire: Happens occasionally, especially when Seidou plays against particularly sympathetic teams. Most notably against Akikawa and Ugumori — the latter being notable in that it managed to warrant this reaction in-universe from the game audience, due to their big underdog qualities such as coming from a smaller school (or at least not an elite one), optimistic disposition and a classic tearjerker sports backstory. Notably, this happens less frequently than other sports manga and anime since Seido as a whole is by far the most popular team. The official popularity poll ended with nine of them in the top ten, only Narumiya managed to sneak in at seventh place.
Squick: The way Coach Kunitomo of Inashiro keeps cracking his neck is...unpleasant
The Scrappy: Ochiai. Mainly for his Jerkass attitude, blatant favoritism and Tyrant Takes the Helm tendencies. This reaction calmed down since Act II, as he becomes the coach together with Kataoka instead of replacing him, and his approach to the team, while still more logical and results-focused than Kataoka's, has mellowed down considerably.
Eijun is usually energetic and cheerful, but when he takes a hit, he takes it hard, and it's nearly impossible not to feel sorry for him. Two examples in particular would be: when Raichi hits a home run out of his pitch, and when he accidentally hits Shirakawa in the head during the Inashiro game, which later causes him to develop Yips.
Furuya. Before joining Seido, his teammates refused to play with him because he was too strong, leading him to train all by himself.
Raichi, is like Sawamura, energetic and cheerful, but when he takes a hit, he takes it hard, and it's nearly impossible not to feel sorry for him. Raichi also grew up poor, constantly trained with a extremely heavy wooden bat since he's little to the point that his hand became messed up, while his mother left him and his father. Because Raichi's father didn't have the money for it, Raichi was never in baseball team until high school. Raichi is also most likely the only character in the series that does not have a phone of any kind. He doesn't seem to have friends at school as well since his clasmmates didn't think much of him until they saw him during a match.
Ugumori's manager Nao Matsubara. He was hoping to have a bright future in high school baseball, but had an accident in his second year of junior high which confined him to a wheelchair, ending his career as a player. The scenes with him getting the news at the hospital are... rough. He however chooses to support his team as a manager and take them to Koshien, which also makes him an Iron Woobie.
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