IMHO, there's no such thing as "a good all-purpose tire for rail trail/winter road use". The demands of the two riding environments are different, and what helps one, is detrimental to the other--assuming that your rail trails are gravel, like they are here.

What makes a tire good for the road--rounded profile, no tread--causes it to sink in gravel. Grippy nubs (not to be confused with knobs) on a flat profile help a tire float over gravel, but they significantly reduce the contact patch on pavement, and makes any sort of wet, or even damp, pavement extremely dangerous.

I've learned this the hard way. I ride cyclocross tires on gravel, and road tires on road. And studded snow tires below freezing, because there's always a little patch of ice that mysteriously doesn't get salted away.