The year begins with Taurus.
I agree that it must begin in an Earth sign, but Capricorn is too climactic to be a beginning. And Ares is not a begenning either, it is the glorious upswing end of the... the... the lfcycl.
Ares is far more contemplative than calling it a beginning gives it credit for. At the end, ready it is to tear it all asunder, contemplatively so. Power, the power of a whole year behind it. And the fire, the destruction, is the final act of fertility for Taurus, where slowly it all begins again. Like a lazy awakening.