Hi. When it comes to applying to university in the UK, Oxbridge included, supercurriculars matter far more than extracurriculars.
Supercurriculars are activities that you do outside of school that are directly related to the subject you want to study at university, in your case English.
Extracurriculars are any other activities you do that are not related to English.
It is generally advised that only 10% of an Oxbridge personal statement should be on extracurriculars, meaning that your supercurriculars are what's really important.
Mostly, supercurriculars for English are reading. Reading a wide range of time periods, genres, and different types of texts (not just reading novels, but reading poetry and plays too). Reading novels/articles about the ways of studying literature. You can also listen to podcasts or watch TV shows on literary commentary.
I'm sorry to say that your editing course and beta reading are extracurriculars. That doesn't mean you can't mention them, but they're not that important. They do show passion in a different way though, so I wouldn't say don't mention them at all.
I would have a look at the Anyverse YouTube channel and website as they break down how to write a personal statement with examples for different subjects.
With your personal statement, you need to show progression. So one book piqued your interest because of a particular theme, which lead you to read this book from another theme period to see how it explores this theme, and then you watched a documentary about it. To put it simply, there's a lot of "I did _ which made me think _ which lead me to _."
Based on this, you might want to mention more in your personal statement than just the works you've already stated. I also think that once you begin how to craft a personal statement, you may end up finding that you can't really tie in those books to anything else (at least that's what I found).
I assumed that there were some novels that I was definitely going to mention (Mary Shelley's Frankenstein for one), but when it came down to it, I realised it wouldn't work.
I'm applying to university for English and History later on this year, and so I've mapped out a rough idea of what I'm going to mention in my personal statement so that I can see what supercurriculars I still have left to do.
Doing this has led me down a completely different path with my personal statement than I originally thought would happen.
Originally, I assumed I would primarily mention novels, whereas now I plan to mention two poets (one 20th century and one 18th century), three playwrights (one 16th/17th century, and the other two classical Athenian), and one novel on the influences on one of the playwrights I'm going to mention.
You may find yourself doing more than this as you're just applying for English whereas I plan on applying to a joint degree.
I hope this helps, and if you have any more questions, feel free to ask me. 😊