Interestingly enough, I feel that your grammar is pretty much spot on perfect, at least from this excerpt. It's the cadence and rhythm of the way you write and format your sentences that subtly suggest you're not a native English speaker.

Maybe the thing that most sticks out to me is saying "English writings." I don't think a native speaker would say writings, just "in their English", or perhaps "In their written English."

Your English is fantastic, this is me simply musing on what you're suggesting.