The pronoun creates no image itself-- it is a grammatical device to refer back to the tiger. As you said, your language has none, so there must be no contingent image: whether it is said in English or Korean, it is the same tiger doing the same thing to the same cow.
A: I see a big, yellow-and-black cat. B: I see a big, yellow-and-black cat. C: I see a big, yellow-and-black
A: I see [ that the tiger is running toward the cow.] B: I see [the tiger that is running toward the cow.] C: I see [ the tiger, which is running toward the cow.]
of course, I know the difference of that sentences among them. But, the final image of the sentences is same.
In B, I see more than one tiger. A & C are the same image (in spite of the comma, these two sentences are the same-- the comma is an artificial adjunct).
I think you should wait for another opinion about 'images', though, Uamrich.
For me, in your first 3 sentences, 'that' and 'which' are imageless.
In your second 3 sentences, the 'I see that' structure gives me a strong sense of another person; 'that' and 'which' affect the tone of voice of that person.
A, for instance, is a considered, perhaps rather humorously dry statement.