Depending on genre, the choices used for an anime's music and score should fit the setting and theme. I know I'm a huge synth guy but, it doesn't always necessarily have to be synth or ambient. The Irish Celtic Music used for the introductory title bumpers for episodes of "Fairy Tail" actually suit the quasi-Medieval fantasy world setting quite well. In other cases where the story in question is in a modern setting ( less rustic ) with a more sentimental tone and fewer comic elements to it, I think this obscure little gem pretty much typifies the sound that I would be looking to implement into the soundtrack of the hypothetical anime series/film. By some people's questionable tastes, this would actually be considered rather "kitschy." Yeah...whatever.
"Girls In Cars" by Robbie Dupree