I like tow rings as front tie downs, even though they are typically pulling the canoe forward. If the stern tie points are also pulling forward \-------\ I tie a short length of rope between a thwart and rack crossbar pulling (holding) the canoe backwards.
Without some oppositional force driving downhill on a washboard road to the river too often resulted in the canoe(s) walking slightly forward, noticeably from the suddenly slack bowline.
Tow rings, while uber sturdy tie points, can have other issues. Some rings are right angle rough hard on rope and benefit from a large carabiner for bowline longevity. Same for the rough metal on some trailer hitches in the rear.
Some tow rings are so far under the bumper that it is hands and knees to pass a rope through, not fun in mud, or when your knees get so old that getting back up is a challenge.
Our old CR-V had decently smooth tow rings, reachable with having to crawl under car, but the front of the hood had a \__/ shape and the tow rings were close to the edge. We discovered the hard way that bowlines could (would) slip past that angled edge and quickly burn through while rubbing against a front tire. Surprisingly “What the hell just happened!” quickly.
The immediate solution was to cross the bowlines in an X; the better solution was to install under hood webbing ties.
And some vehicles offer no viable place for an under hood webbing tie. A friend has a high-roof Ford Transit cargo van. Every “bolt” at the edge of the hood is plastic. Not just plastic, but plastic bolts going into a plastic frame. I wouldn’t trust plastic bolts, much less plastic bolts into plastic housing. Next solution. . . . .
The edges of the engine compartment have runs of various wires and tubes everywhere a flexible hose and webbing tie could be placed, at least without the bowline interfering with the windshield wipers. Ford did not design that vehicle with bow line use in mind.
The next solution took us way too long to figure out. The bumpers are, of course, plastic, but behind the plastic is sturdy metal. Even better, the bolts for a license tag are beefy threaded hex heads. Same webbing loop with a melted bolt hole as under hood ties and presto, we didn’t need eye bolts, or newly drilled holes.
PB030010 by
Mike McCrea, on Flickr
Fortunately his State does not require a front tag, but if it did the loops could be made just 1” long, so they didn’t dangle when not in use, obscuring the tag.
The bowlines off tag bolts clear the wipers nicely, and the license tag loops provide always-there tie points.
PB030014 by
Mike McCrea, on Flickr