As a writer who taught English at the high school for 34 years, you have hit the important uses for quotes in dialogue.

Over the years, I have also helped several writers as either a writing teacher or a friendly editor (I didn't get paid.).

In one particular case, I addressed the writer's use of single quotation marks in the dialogue written and that the writer should be using double quotation marks. The writer insisted that his publisher wanted direct quotations marked with single quotation marks.

As a reader, it was frustrating and confusing to read as piece of dialogue that looked like the following quote.

'I can't seem to find the flashlight,' Mary said. 'It isn't in the drawer where I keep it.'