To add to what EZ has said, I would also warn against naming any books/authors/examples in the introduction - I wouldn't even name them in the topic sentences. I've only gone as far as saying something like 'Social parallels and literary works such as Carson McCullers' 'Member of the Wedding' delve deeply into these ideals...' towards the end of the introduction, and even then my teacher told me to avoid naming the book just to be safe.
In terms of getting a 20/20 for a context piece, I definitely didn't have the top-tier writing prowess or skill like Viva or EZ - I wrote a straight, formal expository essay that included an external example then a book example in each paragraph. Basically what I did to make the essay stand out was to look deeper and further than just saying that '____ shapes our identity' and '____ leads to belonging' but coming up with ideas that are much more complex than the words of the context (which is a huge trap for identity and belonging). Also little things like comparing/linking characters'/people's experiences throughout the essay, even if they're not from the same book or example etc, to demonstrate how the ideas can be applied universally. And overall, examiners want to see complex ideas over complex language - explain complex ideas using simple language (but try to embellish with a few 'big' words here and there), not the other way round... It is rare to see an essay with complex ideas AND complex language that is done extremely well, eg. the likes of EZ.
I'm not saying there is a right or wrong answer to context essays, this is just my approach to getting a perfect score in it... All in all, it's about having a pool of strong ideas and examples that you can easily delve into!