The following is a short elaboration on Planning Pirates Events for Battlefield Pirates 2. All the principles there hold, with some modifications.
Duration
As opposed to the Refractor 1 engine used for Battlefield 1942, Refractor has poorer support for large vehicles, and is much more focused on infantry-combat with weapons with clips. As such, naval-combat is slower and more limited, and infantry-combat less snappy. Therefore, map-duration in this mod should be longer to accomodate, with a round time of 35 minutes, with a 5-minute buffer, though still played once with a regular ticket count.
Variety
Like the game itself, the 20+ maps work best with an infantry-focus. That is, the confounders in this mod are mostly Large and Massive maps in Naval-mode, with a decent crowd-size of 16+ players. Otherwise they lack the necessary interaction to drive engagement.