Here are a few things usually not mentioned when comparing the sailboat to fishing boats:

* Sailboat requires a large amount of labor to make AND maintain and upgrade. Maintenance materials require glue, which is more time spent gathering lobsters and such. If bought from the marketplace, recharge costs 400k per 100% sailboat power, but much cheaper at port. Upgrade equipment costs a few million silver per piece for very little actual gain.

* Sailboat is awkward to accelerate, turn, and stop. These are mitigated by the sailing skills somewhat, but that requires additional time spent sailing or taking the ferry to Port Ratt for the daily quest (1.5 - 2 hour round trip). Ideally, you want to do this as much as possible before you finish building the sailboat, and will probably take 2-3(?) weeks or so just to get to Skilled 1.

* Fishing boats are much more practical to have at every port, or for multiple characters.

* fishing boat: 174721 lifespan, 15 per 6 sec = 19.41 hours constant sailing
* sailboat: 1 million power, 1500 per 8 sec = ~90 minutes; using skills depletes this faster.

Of course, the sailboat is "rechargeable," but it's a bit expensive to do so out of port. The sailboat is undeniably faster in a straight line, but it's mostly made for port-to-port trips, or for situations where you need more durability and cannons (Margoria). Building and working skills for the sailboat is a fun adventure in itself, but if you only take short fishing trips and like to park on remote shores, fishing boats may do the job just fine.