The thing about shonen is, is that it is very good when the mangaka is competent and knows how to apply the genre tropes well. Two most important things shonen should fulfill are 1) a colorful world 2) cool, but likeable characters who may belong to conventional character types but they are not card-board cutouts. Basically, they have heart, to put it in shonen terms.
That is why series like One Piece, which fulfills both criteria exceptionally well, is a massive success and continues to be loved, while others fail. This series passes both requirements with flying colors. If this series was serialized in Shonen Jump, it would be very popular.
Another positive of the series is that the female characters are good. They make up a respectable portion of the cast and are well written. It should be something that all writers should be able to do, but it's quite sad how many don't. Considering this fact, and the name Kairi, I believe the mangaka may be a woman. I don't want to compare, but this mangaka brings to mind Fullmetal Alchemist's Hiromu Arakawa, particularly her earlier works. This mangaka's newer work, Rex Fabula(Kyouko no Ou), with its darker, psychological tone, particularly brings to mind FMA's willingness to tackle mature subjects.
I hope that success comes to this deserving mangaka as it had to One Piece's Oda and Hiromu Arakawa and that this manga will continue to be good when it returns from hiatus (although I really like Rex Fabula as well).