Originally Posted by DoctorNarrative 
If it's load screens at a certain point but one large map then okay fine. If it's completely separate maps though and you just sail your boat automatically from one to another that is a little disappointing.
There's actually no difference if you think about it. What does it matter whether it's one map or multiple maps if there's load screens anyways?
Not having manual control of the boat sucks, but it's not a deal breaker. They announced that early on so it's not coming as a surprise.