I'm going to contend that paganisms are preeminently religions of land, lede, and lore.
Land. Paganism is local, intimately related to specific places. Pagans are by definition the People of the Place; when peoples change their place, they bring their mythologies with them, and those mythologies naturalize to the new place. While the term “nature religion” is problematic on numerous levels, the paganisms direct themselves largely to this-worldly concerns, and engage the environment and the non-human beings with whom we share that environment as a matter of primary spiritual course. There are no universal paganisms; or, rather, the paganisms are at their most universal insofar they are most specifically local.
Today is the third (and final) day of my official mourning for my heart-friend and partner-in-arts Sparky T. Rabbit. For three days now I have neither bathed, washed my hair, nor shaved. I've worn the same dirty clothes every day. (Fortunately, the nature of my work permits this.) I look (and probably smell) terrible. It's a kind of shared death, a time In Between.
I learn something new every time I encounter these old, ancestral customs, usually by way of seeing the deep wisdom embedded in them. In this case, the sheer physical and psychological discomfort of this disruption to normal life is strong incentive to move through deep mourning and into what comes next.
Sparky, I know that guys with beards always made your heart beat faster.