Assalamu Alaikum wa Rahmatullahi wa Barakatuhu ya Ukhti Humaira,
You are probably in a better position than any of us to judge the ramifications of a Pakistani/Moroccan marriage, seeing as your uncle is married to a Moroccan lady. Try to sit down with him in a private area and seek his advice openly and honestly, being willing to hear both negatives and positives. Stress to him how important it is that he give you guidance. Remind him of the Prophet’s hadeeth wherein a woman came to him seeking advice as to whom she should choose, between two suitors. Normally, it is forbidden to backbite people, but when serious contracts are being considered, the right of the one who will live with the results of the contract outweigh any saving of face to the potential contractors. The Prophet, peace be upon him, said, "As for so-and-so, he is broke, without the slightest property to his name. And, as for so-and-so, he never takes the stick down from his shoulder (i.e., he is the type of man whom one could easily imagine beating his wife.) He advised her to marry neither, in essence.
You are correct in your observation that the dynamics will be different with you, as a female, entering their fold. Families vary tremendously, and it would not be fair of me to set forth a ‘probable’ scenario. You must consider things like the general social status and wealth of the family, I am sorry to remind you. If you are coming from a significantly more affluent background petty jealousies may be a fact of life that you would have to live with if you married this man, however sweet he is. Remember, you are not marrying an individual; you will be bound at the hips to his sisters, mother, aunts, and other persons in their circle. If they see you as a spoiled little outsider, things could be bad. If they themselves are quite well off and, generally, well educated, it may not be an issue at all.
I am an American married to a Moroccan and, here in the US, I have seen many many mixed marriages. There is no hard and fast rule. But remember, the Prophet (peace be upon him) strongly suggested that people seek ‘al kaffa’a’ in marriage. ‘al kaffa’a’ means sameness and fitness; similarity in backgrounds. You are only nineteen years old, ma sha Allah; you have your whole life ahead of you. I urge you to finish University and whatever other educational goals you have set for yourself before you contemplate marriage. Being a wife (or, a husband) is not an easy thing. It is not all roses and poems and starry eyed encounters.
I do wish the best for you in everything you undertake. I would not make any decisions whatsoever without cornering your uncle and gleaning whatever information there is to be gotten from him. Also, watch his wife and how she treats him and others in your family. Appraise her character; her brothers and cousins may share many traits with her. Ask her, directly, what she thinks of her cousin; what are his prospects? Does he want to stay in Morocco? Is he a hot head? Real husbands and wives have to deal with many a difficult situation; you want someone with the mettle to withstand the onslaughts of time and changes in fortune.
Gotta go now; good luck.