I just wanted to add my 2cents into this discussion.
Of all the ships would'nt the oil-tanker should have more bellowing plumes of black smoke? Since the AI isnt affected by the smoke screen (it would be good if they were) it would only count as an enhanced effect, but in multiplayer if u have a oil-tanker bellowing alot of thick black smoke- it could be good for cover- for those who are taking a beating of course. And if there are a few oil tankers burning/sinking in the area- the visability will be poor for everyone in the immediate area for a short time. Which i think would mix things up- make it more intense- such as surface ships having to slowing down and being carefull to avoid collision with others. Relying upon your tatical map, until the smoke begins to thin out.
However most ships sink fast, maybe alittle too fast, which would help the lag factor with slower running computers when in multiplayer perhaps.
Anyway, i was hoping to see more black smoke and flames, perhaps that will be the case in the addon/update in the works.