Depends on if you are repairing a set number, or a percent of hull per second. That would flip it, making it most useful on Galleons, least on Squid. A fair medium would be to add n+(h*.01) per second, n being a flat number, and h being max permahull. Squids would gain the most out of n, while Galleons would gain the most out of (h*.01).
And again, buff hammer needs to stop adding damage. That would solve so many balance problems.