I think these are new questions, and while I am not sure that your answer is WRONG, 'quite important fishing port' certainly sounds better and is more correct in English. If you said 'a fishing port THAT IS quite important' I'd agree with you, however we could probably construct the French in the same way.

The cards don't always have the words for the main translation, just one of the acceptable translations.

"Assez" may be translated as "rather" or "quite" or even "pretty" to slightly emphasize an adjective. So you need to be aware that the little word-tiles may use one of the other accepted translations. There is rarely a single word-for-word translation. Hint: play the cards you're dealt.