Wiccans are a pretty diverse group of people in terms of their theological views. Some are atheists who see it as a system of symbolism, some believe in gods as forces of nature. I don't believe that many Wiccans are pantheistic, though. Most are more deistic, seeing their gods as representations of forces.
Wicca was created as a form of Celtic reconstructionism, but it isn't the most accurate reconstruction of it. Modern Druidry has more in common with traditional Celtic Paganism. It's not rooted in Shamanism, as far as I know, that came from Russia.