The better the school, the more difficult it is. As long as they meet the standards of professional courses and language courses, they can be promoted directly. There is no fixed quota. If you don't want to go to other better schools, you usually need IELTS scores. In addition, there are professional courses and overall requirements.

Nationality of international students

The British don't go to preparatory school. If you want to know the English, it's impossible. Students are generally international students (Russian, Indian, Southeast Asian, South American, China).

Relevant work experience plus points

First of all, having relevant work experience is definitely a plus item, but your so-called hard indicator refers to the results of four-year undergraduate courses, right?

The purpose and choice of studying abroad

Whether to study in preparatory school or study abroad after work depends mainly on why you study abroad and what is the purpose of studying abroad. If you want to experience more foreign life and adapt to it, you can choose preparatory courses to make you more adapted to British education. But if you just want to get a diploma, I suggest you don't waste time and money, just study for a master's degree.