Well, it depends on the person's requirement. It is not necessary that person has many requirements. Well as per mayzus is a good broker. But it has more spread than instaforex. But as per payment process mayzus is better than instaforex. So a selection of a person is necessary.
I think the requirements needed should be things that could attribute to more profits. For me the basic requirements needed in a broker should be being regulated, fast payment and low spread. Other additional thing should be bonus and it attributes no much to success.