The previous owner may have had the right idea. Repairing these cosmetic issues can result in a bigger mess. Here there is separation and chipping of an overly thick gel coat. It's not something to worry about structurally but it does detract from appearances.
If you have never used glass or laid up gel coat to sort out one of these canoes, you should be aware of a couple things.
It's fussy work to make it blend and it's well within most folks abilities to do if you take your time.
The biggest problem you will have will be color matching. If it were me and if I were going to try to improve that, I would be planning to re-paint the entire deck after the chips are sorted out. That's me. You could also try to use dies to color match, but do so knowing that whatever you do, it will be visible to the critical eye.
Step one, remove all of the chipped gel coat.
Step two, carefully fill the spots back in. Use either glass resin, body filler or West Systems thickened G-Flex. I'd probably use the G-flex because of the long cure time and how easy it is to shape and color.
Depending on the amount you build, either sand or file to smooth. You will need to repeat this process several times to get a decent result.
When you are happy with it, mask everything around the decks and paint. I would spray, not brush.
The challenge to achieving an as new appearance is that the gel coat was originally finished in a polished form as a build up layer. There is no way that you can duplicate that now. And, paint is not going to resist scratching and use the way that hardened gel coat has.
WRT tiedowns, I've used wooden braces jammed under the rails inside the hull near the decks to use as tie points for bow and stern lines for car topping.
For use on the water, think about bonding a couple tie points in.
