Air Gear is a sports manga with maneuvers that scales exaggeratedly for action, this ends up being a problem and a quality. But let's go by parts.
The characters are very charismatic and stylish, in this the author is quite right as he gives each one a moment to shine in a way that makes them stand out.
My favorite is Kazu who grows from a mere supporting character to one of the best in the work. Other than that, there are still female characters who really have personality... Unlike many manga who simply see them as an escort for men, here they have their own space looking for their own goals.
The protagonist, Ikki, is kind of bland. Of course, in terms of having cool scenes, he delivers smoothly... Only something is missing that makes him stand out outside of being the most skilled, because his personality is dull and he never manages to add to the participation in the story beyond the cool scenes. It lacks presence, a little charisma and a little substance in it.
The story is problematic, the beginning is quite disorganized simply dropping information without giving context or construction to the world so that nothing feels really connected. That said, it still has a certain quality to it since the author throughout the story uses some element thrown into the plot in a way that has relevance within the work that creates a feeling of having some planning on his part.
That said, the story still fails to have a very clear path and follow a very different path from the initial one. It starts with a story of street sports with maneuvers for an action where each maneuver creates a super power... Due to the author's art, which is at a high level, the fights are always exciting, but in terms of the story, it causes a great strangeness.
Art is very good, Oh Great! he is one of the best artist today and here he already delivered very elaborate pages of action or visual allegory that gave a great narrative impact.
Finally, Air gear is a manga with fantastic art, but with a poorly structured story and a disappointing ending. Not only good art can make a good manga.