Giant Killing is somehow a soft show, not intimate but close enough, in a way, and there's an overall nostalgic feeling about it. There isn't any spectacular ambition showing, nothing is really fancy and the viewer's emotions rely on the story in its unraveling, more than on an audiovisual ride. Be it the art, the animation or the score: we're miles away from recent blockbusters like Kuroko no Basket or Haikyū!! Fortunately, the story here is better than in many shōnen in the sport category.
About the art, you will probably notice that the chara design's focus on noses is very pronounced, and literally adds a fit sharpness mirroring the treatment of the characters, intensifying each personality. So, even if you should find the chara desin unattractive or old school, paying attention to that particular detail may help you bear with it in an interesting —and not-so-common— way. At least until you get familiarized with it.
Despite following a rather slow pace at times, and despite not being as tricky, gritty and inventive as its baseball counterpart, the show's action is always both interesting and entertaining, and is supported by many likeable characters. Still, something is lacking. The narration tries to keep it real, goes seinen and refrains from showing-off; but most characters in the show are presented under a positive light. It almost feels like watching Winnie-the-Pooh and his friends playing soccer! I exaggerate, of course, but that positive feeling, even if very enjoyable for the viewer, tends to soften the treatment and minor every dramatic event. When you get where the story is heading, 26 episodes seem a bit short and frustrating, but as the show progresses without switching gears despite any occurring event, you realize it may eventually be for the best. Because you're not sure you could follow some 52 to 100-episodes saga with that kind of pace.
But don't get stuck on such pessimistic impressions, if they should ever come up. Because in the end, when you'll be watching the last closing credits of Giant Killing and it will have turned out the 26-episodes course was really for the best, it won't be out of disappointment or frustration. At worst you might feel a bit nostalgic.
But you will know you just watched a good story.
