this manga is not one piece. it doesn't have the same story power, nor the character strength. this manga is similar to one piece only in art, which is deviating away from one piece and into a uniquer style as time goes on.
pros: the mangaka, as with his past works, has a greater core story in mind that reveals itself within and inbetween the arcs. if past history can be used to predict future outcomes (and it usually cant), then the core story of fairy tail will be pretty cool and tie together the entire manga in a fairly effective way. furthermore, the comedy in this manga keeps me entertained and adds to manga in a positive way, not in a distracting or negative way.
cons: the individual arcs themselves are riddled with shounen cliches of the worst kind. notice that I make a distinction between some cliches that are bad, and others that are good/acceptable. the acceptable cliches are things like the story being an action adventure based around a super strong but blunt protagonist who has quirks that add comedic value. we've seen this in dragonball, one piece, etc. these kinds of cliches are overarching, which means they are consistent through the entire manga and they are not used to advance or create the plot, they are personality cliches inherent to a character.
however, when you start using plot cliches, this is when the manga dives into unacceptable/bad zones. an example of a plot cliche is the old fashioned "evil character suddenly turns into a saint and only wants to do good things now". don't misunderstand this to be another cliche that is overarching to the character, normally these heel/babyface turns are the focus of an arc in the manga. therefore if you focus an entire arc around a cliche so tired as "the turn", it completely ruins the credibility of the arc, the manga, and the story all in one fowl swoop. and i have merely provided one example. the arcs of fairy tail are littered with these story-centered cliches which really REALLY take away from the plot. any generic shounen action will give you fights, cool powers and characters, etc. i can find these things in ANY shounen action. what differentiates one shounen action from another is the characters and the plot (and many times the characters are so similar to other shounen cliches that plot is really the only thing left).
if you start bringing the plot down to banal levels that i can find anywhere, why should i care about this particular one? well i'll tell you why. cause after some time has passed, a fan like myself gets attached to the characters and attached to the world in the manga. so therefore while adding terrible plot cliches won't make me stop reading, it will certainly make me not appreciate this manga more, nor will it make me view this manga in a greater "epic" light that I view other works that I deem are incredible. and so finally here we have fairy tail. a world that provides me with enough enjoyment and attachment to continue reading, but not enough to rise to the level of epic like one piece has done. for this, i give 7/10
BONUS EXTRA REVIEW MATERIAL PART DUEX: comparing one piece to fairy tail (since this seems to be what most people who review this manga like to talk about)
one piece is so much greater than fairy tail because the story and arcs of one piece, while they contain some of the plot cliches that i absolutely hate about fairy tail, the degree of dispersal in the arcs is limited. and on top of that, the extra awesomeness in the arcs of one piece somewhat remove the negative effects that the plot cliches create.
if you remember my "pros" for fairy tail, i mentioned the core story that will wrap up the entire manga in an effective way. this is also present in one piece. sometimes you see a character that appeared in literally one frame of an early volume become a central character in the later volumes (luffy's grandpa, silvers rayleigh). this type of long term planning and consistency contributes greatly to the credibility of the manga and the core story.
furthermore, the individual arcs of one piece have a greater focus on adventure than fairy tail. a typical fairy tail arc is focused almost entirely on unity and friendship. while you see these same traits in one piece arcs, once again the degree of dispersal is limited. while friendship or protecting his nakama is usually the reason luffy fights and wins, the majority of the arcs involve exploring new lands and meeting new characters.
the ultimate example is sky piea. the degree of innovation involved in sky piea is stunning. here we have a world that is completely developed, right down to the fashion, technology, lifestyle, political structure, etc. almost anything you can imagine a new exotic land to have, sky piea has it. this degree of thought and consideration is practically unheard of in an arc. many mangas have this degree of thought and consideration, but only in the CORE story. the overall world of the manga. not just 1 simple arc, but the ENTIRE world. yet here, we have a single arc and it has the same thought and consideration as an entire manga world would have. and we see this in multiple arcs in one piece.
and so now we get down to the meat of why fairy tail is no one piece. fairy tail's arcs are too focused on friendship, protecting friends, and unity. it's 1 thing to have these elements in an arc, it's another to have them as the focus of the arc. one piece's arcs have exploration and new elements as focuses, this is why it seems so fresh even after 600 chapters. the new worlds we see in the arcs are all fully developed and fresh. i'm too distracted with the awesome worlds to see the repetitive cliches like friendship, protecting friends, etc. in fairy tail there is no such "awesome distraction". and so when you don't have that present, i'm left with constantly thinking "ok, you are friends, you are a guild, lets move onto something new". and as time goes on, fairy tail seems to get more and more focused on these plot cliches, and thus has less substance in the plot. one piece is an epic for the reasons stated, fairy tail is not for the reasons stated. thank you for reading my review, have a nice day.