Although I don't identify as Reform and thus can't be accused of bias toward it, I would've ranked Rabbi Eric Yoffie, not Marvin Hier, as #1.  Rabbi Yoffie is, after all, the primary spokesperson for what is now the largest Jewish denomination in America.  Not to devalue Rabbi Hier's important work, but it seems to me that R' Yoffie's name pops up much more frequently when media types want a "Jewish perspective" on something or another.