This is a useful post for evaluating whether you are a high stats applicant compared to the majority of UCB applicants and admits: Admission and yield rates by college (L&S, CoE, CoC, CNE, CED) and HS GPA
It’s a bit mysterious which students are selected for the LOR request, but it’s nice to have the opportunity to add LORs to your application, if you have teachers who will be happy to write them.