Yeah, I've done that, no issues. Though technically parks close at dusk and in the winter it'd be dark by then. I think most of my after-dark walks have been more in the city itself or over to the riverfront. (Though that might also technically be closed at dusk..?)

I feel pretty comfortable with the standard "be aware of my surroundings" that I employ by default outside after dark, and haven't really felt the need to have anything more stringent like I might in bigger or more known-dangerous places.