[dogscoff]

...gunboats... but for game purposes I wouldn't see a problem given the small number that could be launched this way. You could also have fireships launched in this fashion or as drones.

You could have them launched from ports onlly.

One of the main problems with converting se4 to a ships & sea game (apart from the extensive graphical modifications) has been the difficulty of representing "coastline". You can get round this, of course, by having nothing but open sea witrh a number of small islands (planets) in it. This seems to be the approach you are going for.

However, I wonder if it would be possible to
generate all non-oxygen planets with a massive sector damage ability, so that any ship sailing into "land" is instantly destroyed. You could have huge blocks of "mainland" like this, with oxygen planet "ports" on the edges (ie "the coast"). You could also have uncolonised "ports" which could be settled (caves and harbours to be turned into pirate/smuggler hideouts) and which, over time, would grow into full towns/ ports. (Assuming you build the right facilities and cargo units.)

Of course getting the map generator to place all these items sensibly would probably be nigh-impossible, so these maps would almost have to be hand-sculpted.