What connotations can you find?

Navy boys keep coming inside them, and they are full of seamen.

Mighty, powerful, headstrong.
Capable of holding themselves (and perhaps others?) in rough situations? It's hard to say when I don't know the character! Which character are they, and from what text?

A fantastically witless response. A* for lack of creativity, you did so well.

It is the chapter named 'Swelter' from Mervyn Peake's Titus Groan, of the Gormenghast trilogy.

And thank you, I had something similar in mind.

Also stubbornness - 'great ships are slow to turn'.

That is a beautiful illustration of the connotation of stubborness in terms of that metaphor. You win all the points, bravo!

The irony would be that a 'great ship' would actually require significant direction, guidance, supervision and input from many others.

You could also compare to Helen of Troy, who was 'the face that launched a thousand ships' - whereas this person is being compared to the ship itself.

You are in a different league my friend. I wish I was as imaginative as you, or even half that.