It's perhaps not very "weighty", but I really like Agatha Christie. The language is good and regular, without too much slang, and is generally still modern enough to represent standard English today. She wrote a lot of short stories, which are always good because it makes the task less daunting. And above all the stories make one want to read on while paying close attention. I recommend you start with "the Thirteen Problems", which are 13 short mysteries starring Miss Marple. Agatha Christie did write a lot other than Miss Marple and Hercule Poirot, though. A nice alternative is the Parker Pyne stories, or (a bit more challenging) Harley Quin. If you don't like mystery stories though, you can leave these alone!

Take a look at this list ... https://www.penguin.co.uk/articles/2018/100-must-read-classic-books/ A personal favourite from this list is The Chrysalids, and another is To Kill A Mockingbird :)

A book that I strongly recommend is “Call It Sleep” by Henry Roth. It is the story of a young boy who immigrates to the US with his mom to join his father who has been living and working there for some time. The story is set around how the boy perceives his new life and the book is written with a very subtle technique that makes it a bilingual book; the author has used English in a very skillful manner to make the characters communicate both in Yiddish and English without having to highlight it through the narrator. Reading “Call It Sleep” is an astonishing experience.

To kill a mockingbird Animal Farm

It is a modern classic but you might like The Handmaid's Tale by Margaret Atwood (which is now also a film).