There shouldn't be any real reason that the diet of any breed of rabbit is dramatically different. The only factors that really need to be taken into account are the size of the rabbit, the age of the rabbit, and any medical issues. As complicated as it can sometimes sound, rabbit diets are pretty straightforward. Hay is always necessary, supplemented with high-quality pellets and the correct amount of daily greens for an adult rabbit's body weight. High-quality pellets should offer all the protein a rabbit needs, which is the only concern I have heard of with angoras. Overdoing the protein content of food will likely have more detriments than not supplying enough for optimal fur quality. Maybe you'll want pellets on the higher end of the average protein percentage, but I wouldn't go above that number.
Grooming will be different than most rabbits, and far more intensive. I would also be very careful to keep an angora's spaces particularly neat to avoid anything getting caught in the floof. Some people keep their angoras clipped, which likely makes grooming far easier, although I am not familiar with whether this grooming method is generally considered beneficial.
