I don't think there is much to worry about regarding the stupid sheep jokes, least in this part of the world, not something that is really looked upon with disdain anymore.
As already mentioned predators are big time problem, really big, depending on where your surroundings. As sheep graze closer to the ground than most others, they are much more susceptible to things as bugs and soil borne diseases like anthrax, again this is more prevalent to some areas.
I have heard is that you never want sheep too close to some other certain types of livestock either, I'd have to look it up as its escaping memory at the moment, but there was even a lawsuit over it not long ago somewhere.
In this area wool is worthless, costs more to have them sheared than you get for it, so meat is the only way to go.
And as also mentioned, where the real money is in the halal bit is if you are located in a good location for it and are willing to provide an area and facilities for them to perform their ceremony. I know a few who do this and while it pays good, its not really something they are comfortable with either but adopt the "out of sight, out of mind" philosophy in exchange for the dollars.
A friend and neighbor used to have about 200 of them, he offered them to me after he had a heart attack but I didn't have time to build the facilities needed to contain them. But I do believe there is a buck or two in them when done right if markets are available. Myself I would never get into offering the halal thing, no thanks. Can be very time consuming during lambing though I've been told.
Contracts are made to be broken, a handshake is the law of God.