Thanks, Tom. This is exactly what I was hoping for. It is a tough call whether to use authentic language and try to spell it phonetically, or to just flavor the language by adding a word or two. I lean toward a little flavoring of the accents and language that are hard to write (and read) authentically.
You point about technical terms is insightful also. Sometimes they are required for authenticity. But as you said, using too much can be overkill for many readers.