Breakwater Seastead
This page should be filled out with the arguments in favor of a Breakwater Seastead (and maybe some against).
Some arguments at BreakwaterBay.
A breakwater marks out a particular territory where some set of rules will apply. It provides a sheltered area, so a service to boats or smaller seasteads that people would pay for (people pay to park boats in marinas all the time). A breakwater makes the individual family vessels much easier since they don't need to handle large waves.