Ghost Hunt's backstory and setups of how the various supernatural forces operate are well done, as well as the actual mysteries they are involved in. However, what distracted its best qualities are the forced relationships and relying on predictable tropes to advance plot elements. My impression is that Ghost Hunter may have been altered to cater to target audiences by dumbing down the plot and dialog at some points, but when the actual investigation storyline calls for complex explanations and logic, the characters inexplicably gains 200 points in IQ to figure everything out.
Case in point: after almost a year working for ghost hunter experts, the main protagonist was told they there were two children of the family being investigated were behaving strangely, and when she meets them, they are constantly repeating about they wish how their relatives would die. While it's obvious to the audience they are possessed, the protagonist is completely oblivious to this possibility until the plot conveniently calls for that moment later on for dramatic effect. Better options would have been to make their possessed personalities less black and white or simply not mention these kids beforehand. Throughout the series contain very poorly implemented scenarios of a) main characters become oblivious to obvious clues, b) withholding key information (i.e., the girl has ESP, gets a vision but doesn't tell anyone about it until the 3rd act) c) unconvincing situations forcing characters to become alone or in danger and d) overtly reliant in chibi style comedy to excuse logic gaps.
The culmination of these effects ultimately makes the main protagonist Mai a every unpleasant character. She's supposed to be the everyday girl, but is stupid while the story needs other plot elements to take shape, super-talented and powerful when when the story calls for a solution, overdramatic to force tension between her and her friends, and is somehow excused from her ignorance because she's supposed to be 'just like us'.
But this is somewhat bearable, since the actual cases they are investigating are truly well fascinating. What made them great was that we cared about the people involved in the cases, we were sympathetic to their plight. Unfortunately, the series gradually moved away into 2-dimensional antagonists and threats in order 'power-up' the main characters.
I was interested enough about the case to bypass the faults in order to find out the resolutions. But really, I just wish they were confident enough in their core story to not have to throw in these cliches to appeal to young kids. I wish the main characters were competent, mature, present their relationships with subtlety, so that I don't have scream at my laptop at that the main culprit is the teacher and not the girl while the characters are wasting my time.