This maybe because of 2 reasons
1. The manga has not reached a point where the story must get serious and bring in a solid plot line or
2. Mashima had never thought much about where the anime/manga had to go, since he planned to end it way back.
One thing I absolutely love about fairy tail is the background music. Its so amazing that it makes even the most useless scenes look awesome, and the art deserves a 9/10 as well since this is definitely one of the best animated long running series till date. The character development is good but could be better. And certain arcs are there just for the fun of it rather than affecting the main plot in any way. The series though in all aspects is very enjoyable and does not have many fillers in comparison. Overall I give it an 8/10
