I've got three mats on order. I was thinking on cutting it down to two mats for this scenario to make it more of a knife fight and just declare the edges solid so no one could run away. This also solves the problem of what do I do with someone's bounty if they sail off the board or what if someone has a huge bounty near the end and they just try running away from everyone?
After seeing that impressive classy Hurricon set-up surrounded by terrain, I'm kind of thinking that would be a less contrived route to take. Go back to using three mats, but occupy some of the space with surrounding terrain to compact it back down and this also gives a plausible reason why you can't sail off the edge of the board. Basically it's a pirate fight in a harbor. I'm going to leave some edge or opening available, though, as every time someone brings in a new ship...it has to come from somewhere.