Cantonese fried rice uses Chinese sausage (or BBQ pork leftovers) and green vegetables and spring onions.
I have added rice wine and chilli slices for more complex flavours. The test of good fried rice is the grains must still retain its integrity and not too wet and marshy. A tip is to use less water when boiling the plain steamed rice or use "older" rice.
In the famous Yangzhou (yongchou chow fun) shrimp and mushroom are important ingredients, with carrot and peas added for colour and fresh taste. That's the main difference.