Personally, I think removing the monarchy is unwise. Yes, they are privileged, but only to the same extent as other wealthy people are , barring the immediate Royal Family, who do have more privileges. However, those privileges are commensurate with their responsibilities to the nation - the ability to eat swans is hardly a great privilege.
Secondly, as a monarchy, it paradoxical makes it harder for an authoritarian state to be established, as it provides a secondary check upon the power of the state. In a republic, the government can say "Well, we were elected, we have a majority, we are serving the people by our actions", whereas, since the current government still offically serves both the people and Her Majesty, that argument can be invalidated for long enough, should the monarch be strong and respected enough (as Her Majesty is) for effective opposition to be taken. In essence, monarchy actually acts as a stabilising force on politics.
Thirdly, we come to the economic argument. Given that, while the Royal Family is maintained by the public purse, it seems odd that there should be an economic argument. But there is. In essence, the monarchy, being so unique and important to Britain, is a massive source of tourist revenue. Don't believe me? Go to Buckingham palace and count all the foreign tourists standing around there. Now, consider that these people will need food. They will need accommodation. They will need transport. Consider each one of those people a £400 pound injection into Britain's economy.
Now, multiply that number of people by 365.
That's a lot of money. A lot, lot more than we pay for our monarchy. Even if you assume only 15% of that is going into tax revenue, and discounting the multiplier effect....that is far, far more than we've paid for our Queen. And God Save Her Majesty.
