Paganism is anything non-Judeo-Christian. Hinduism is most definitely pagan.
However, many pagans do not self-identify as pagan because the definition is based on a negative. Hindus want to be known as Hindus, not as non-Judeo-Christians.
People who self-identify as "pagan" are generally neopagans such as Druids, Wiccans and eclectic pagans. But that doesn't mean the word isn't applicable to additional ground like Hindus.
"Personal choice of practices" has nothing to do with any definition of the term. You do find pagans with lots of different beliefs, but that's not what makes them pagan.
Neopagans follow 20th century religions or personal paths that draw on the influences of older pagan religions..