You know the old expression, "Never look a gift horse in the mouth"? It might be time to apply said principle. Seriously, if the insurance company is willing to write the boat off, then it's time for you to decide would the boat sell for $30,000 (before the toe rail damage)? If not, take the money and run, to borrow old song lyrics. As you probably already know, this is a tough market as it applies to boat resale, especially with winter barrelling down. If you've ever considered "moving up" in boats, now's your chance.
You can buy a lot of boat for 30k, at least a lot of areas.
However, if you feel like the boat is worth a lot more than 30k, then take the check, buy it back for 3k and "self insure" going forward. There's really no logic in reinsuring it anyway as you will have already been paid out once on the boat. You'd have to verify with your insurance agent, but most companies won't reinsure the boat as salvage, and if you find one that does, obviously they won't insure for anywhere near that amount. The "salvage" moniker that get's added to the title greatly affects its value, even though you know it's really only minor damage. Banks, for instance, rarely would consider making a loan with that title.