Higurashi started out really strong - I went back recently and was amazed by how much I liked those first episodes - but longer it went on, the less interesting it became: less willing to hurt the characters and make the viewer squirm, and less intent on preserving the air of mystery and suspense. The second season was especially bad for me, because it felt like an endless, slow infodump where not only was there nothing truly interesting happening, but it actually made the FIRST season less interesting by giving unexciting, undramatic explanations and recaps for its events.
I truly feel that Higurashi was a major disappointment as a series. It was relatively competently done as a technical accomplishment, but it promised so much and delivered so little. Shit was INTENSE at the beginning, really grabbed you by the balls, but it just lost its oomph the further it went, slowly deflated to nothingness when it should have stayed intense and finally gone out with a massive bang.