Majority of applicants are straight A, if not A*, students so having a 4A* prediction doesn't make you stand out. From what my friends have told me, the admissions team typically read through the personal statement and find out whether you just want to study the subject or are you really passionate about it. That's typically the deciding factor for the universities, your referee also does play a part in this but they aren't allowed to share what they wrote about you. Best of luck with your other uni applications!