I listen to mostly Japanese composers so here's the list:
Joe Hisaishi: He comes with incredibly memorable themes. Every theme sounds so different, it's hard to imagine how they could all come from the same person.
Shiro Sagisu: I love his distinctly chromatic and dark style.
Nobuo Uematsu: Like Hisaishi, he comes up with wonderful themes that are beloved in the Japanese video game world (Final Fantasy).