I wouldnt have a boat without nav lights again.
I wait till all the lake lice, and guys without lights, are gone, or dark-thirty.
Its real easy to see the trailer when the marker lights are on, in the water.
I usually dont boat in a place I don't know, so I dont have a spot light either.
Last October went a 'lil too far south, and it was pitch dark at about the AVI, we launched out of the Riverside. (~15 mi)
Dan'l