The average applicant is... There is no average applicant, really. I mean supervisors vary in what they look for. What you really have to worry about is the university.
Many people mistake universities as educational institutions. They are. But first and foremost, they are a business with interests in making money and bringing in funding.
GRE scores serve one purpose: weed out the majority of applicants, and make the process of filtering down to students who have a high chance of degree completion. For most people, GRE scores and GPA are strongly correlated. If one is high, the other tends to be, as well.
Your grades and GRE scores are mainly screened in order to ensure the university will be able to maintain their high entrance averages that they advertise and to secure funding which usually demands strong academic history from student applicants.
If your GRE and GPA are acceptable, then everything else is going to be your personality, research interests, probability of being funded and publishing...