There is a delay when ships spawn on or near you (although its a very small delay you can usually get a broadside in). A good captain should be ready for anything (unless away from the wheel getting cannon rep hehe!).
It's good that they have changed their patterns. It was getting too easy to go out and easily sink the big ships.
I now prefer to take out a crew (anyone welcome to join my crew

) and get in amongst the big ships. You get a bit of damage but so far I havent visited Davy Jones! LOL