And if in doubt, use `[[`. I still get caught by things extracted as lists instead of vectors, and half the time I still don't get why.

Many file readers will take multiple files in a vector. For instance 'readr::read_csv(c("file1.csv", "file2.csv"))'. Good to introduce them to building the list of paths programmatically and to mapping or looping over a list as good patterns.

This happened to me. I was told to redo analyses in Excel so management could understand them. I now work for a group that codes in multiple languages, and is OK with me using R as long as I share, document, and explain my code.