I tend to make my caverns tall and large to make exploring much more fun, but by doing so, caves under oceans look deformed.
A feature to config caves under oceans would be pretty neat.
Or maybe there already is and I'm just a fool ツ.

Example of a normal underground cavern:

Example of a cavern under oceans:

The abrupt walls around the edge are due to the algorithm used to close off flooded caverns from non-flooded caverns. Unfortunately it looks a little jank when the caverns are large.

The large stone strip along the ground is spawned to separate lava regions from water regions. Of course, this shouldn't spawn in flooded caverns so I should probably remove it.

Closing since I no longer support 1.12 actively.