According to G's excel file, Ottomans aren't appearing on coast due to a bias.
In this thread, on the page before this one. He said he looked at Gazebo's ZIP file.
I see now, thank you.
There are 12 civs with a Start_Along_Ocean bias (what we sometimes call a coastal start bias). I'm going to sort them from highest coastal priority to lowest, in terms of unique traits.
These are the civs, which for gameplay reasons prefer to begin the game on coast
Polynesia..............entire identity is water related
Carthage............... entire identity is water related
England.................both the UA and UB need water
Portugal.................the Feitoria needs water to be built, UA also likes coast
Denmark................jelling stones like coast, UA benefits coast to some extent
Netherlands............the unique unit is a ship. Otherwise, zero coastal synergy
These are civs that currently have an along ocean bias, but don't have significant synergy with water.
Indonesia................the civ itself has zero coastal synergy, but there is flavor for an island nation beginning on coast
Japan ................the civ itself has zero coastal synergy, but there is flavor for an island nation beginning on coast
Spain ...................the civ has some exploring synergy, but you don't need a coastal capital to use it
Byz ......................the only flavor is the capital city
Korea ......................this civ would probably prefer not to begin on coast. I don't care if Korea is a penninsula, this should be changed.
I would personally drop the along ocean for all of these, but I can see an argument for Japan or Indonesia keeping it.
Then there is Venice, who gets an even higher priority to be on coast. He probably needs it less than Carthage or Polynesia, but he is also just a weird civ.