To summarize the "priority" importance, here is the list of factors (from the most important to the least important):
1.) TAP (Transfer Alliance Program) - According to many people here, if you are in TAP, you are basically 90% in at UCLA regardless of your major (impacted or not) as long as your GPA is above 3.2
2.) GPA - Applies only to people who are not in TAP. Maintain at least 3.5 GPA for non-impacted major and 3.8 for the more impacted major.
3.) Essay - Applies only to the borderline candidates. This is where you get to "plea" and "brag" about your ECs and/or hard circumstances that prevented you from achieving your academic perfection, and the essay that truly stands out gets the bread.
4.) Employment - Employment matters much more than the school clubs/organizations. School clubs may show your leadership ability, but employment shows something more unique that very few people possess: family responsibility.
5.) ECs/Recommendations DO NOT MATTER.
Whether you agree with this or not, this is as much impression I got through series of discussion and argument regarding "What's the most important factor for Transfer Admission". Although I still have some doubt about #1, I can generally agree with the rest.
correct me if I'm wrong.
#3: nvm about the "bragging about EC" part. It won't do you any good. The main purpose of essay is to describe certain family/personal hardships you had to endure and to explain the reasons for why couldn't do better with the academics.